Fishing suggestions and how to make the minigame more interesting and rewarding are regularly cropping up here on the forums.

I wanted to condense my thoughts and suggestions into a coherent post, and hopefully gather some momentum towards making the fishing minigame a bit more interesting.

My source is my own fishing experiences, having gotten the Master Angler a while back, every DLC fishing achievement, and done some fishing here and there simply for more roes, though that is becoming rarer now.

In order to keep a somewhat long post more easily accessible and readable, I will go over each aspect of fishing summing up the current situation, and offering my feedback and suggestions.

Fishing mechanics
Currently, once you have selected bait, you simply put out your line and wait somewhere between 5 and 18 seconds until you pull back your line. Hm. As many others have said as well, the current system isn't really that engaging, and you're more likely to have YouTube, Netflix or something else running on the side while fishing, or talking to someone on the phone while you do it (which I have done a lot). Simply put, the waiting time in between catches is quickly very boring.
I suggest shortening the waiting time, 5-9 seconds between catches seems alright. But the often long waiting times of 15+ seconds seem to last forever. Ideally, you would have something to do in the waiting time, to participate in the minigame. I'm not sure what, maybe some kind of mechanic that mimics real life fishing, where you have to drag your line and bait across the water or the surface of the water, for better chance of catching something good? Some kind of minigame where you actually had to press some buttons or do something instead of just staring at your screen would be preferable, but it is also the area that would require the most development of an entirely new system or mechanic.

Bait
Ok, moving on to something more simple, bait. Currently you have 4 kinds of bait from various sources, 1 for each type of water. Works great I'd say. However, the 4 types of bait you can only catch from fishing - chub, roe, minnow and shad, those don't work at all. Having to wait 18 seconds staring at your screen, only to essentially trade 1 type or bait for another, is extremely unrewarding and makes people not want to participate in fishing. I actually prefer getting a white fish over the caught-bait, because at least the white fish can be skinned for roe, the caught bait is completely useless and disappointing.
I suggest making the caught bait increase your overall chances of catching something good, such as furnishings and achievement fish. You can also include them as ingredients in rare provisioning recipes. Suddenly you like catching these types of bait, instead of dreading it.

Gunny sack
I don't like wet gunny sacks. I think I have gotten a single Kuta from them from all my many, many, many fishing hours. Other than that, it's simply Ta, Hemming or something other completely useless item. Again, this is superfluous. You shouldn't get crafting ingredients from fishing, when you already get them in huge numbers from decon'ing, refining and multiple other sources. I suggest simply getting rid of the wet gunny sacks, once fishing is fleshed out more as a system, you don't need them in there at all.

Achievement/trophy fish, blues/greens
I feel that this works alright. You fish primarily to get the achievement fish, outside the Perfect Roes. However, once you have caught an achievement fish once, any subsequent catch is just superfluous and frankly you'd rather catch a white common fish for Roes once you have gotten all your achievements.
I suggest raising the selling prices of trophy fish to at least 200ish for the greens and 800ish for the blues. Blues are extremely rare, and greens are reasonably rare. This way at least you can sell them for some nice gold, which makes it feel somewhat rewarding catching them for the second time, or the hundreth.
I like the addition of the purple trophy fish in Orsinium, but I feel it's a pity you didn't include a purple trophy fish for Vvardenfell. Having a single purple to chase in larger zones such as Wrothgar and Vvardenfell is a fun thing to do, and I hope you will revisit Morrowind to add one eventually, and for new Chapters as well in the future.

Achievements
You get a single, pink colour from finishing Master Angler, and can buy the tiny fishing boat achievement furniture. You also get the Master angler title. And that's pretty much it, everything else is just achievement points. A few more dyes would have been nice, perhaps one for every larger zone/chapter, as well as many more achievement furnishings. The tiny boat I really dislike. We have so many fishing vessels in this game now, we got some great ones with Morrowind too, but as a Master Angler, one of the most rare achievements and titles, you only get this small, tiny sailboat that's not even worth looking at. I suggest adding a lot more of the smaller boats and vessels to the vendor, so you can at least choose between some different boat types and pick something a bit more impressive. I think everyone would also like being able to hang fish on a plaque on your wall. The purple Crab Crane fish from Wrothgar, for example, and other rare fish. It would be nice if you could actually hang them on a plaque in your home, instead of the current, bland grey non-descript fish we currently have available as furnishings.

Furnishings
So, currently you can catch regular grey fish, kelp, sea stars, clams, sandcake and two kinds of (small) corals. This is a great beginning. However, I do think we need more fishing furnishings available as well, perhaps even some zone specific ones. Stonefalls has the awesome Vivec's antlers corals, why not let us be able to catch some pieces of that in the Stonefalls zone, and same for every other zone. Many zones have aquatic plants, or harbor related items, or ship related items and such. Let us be able to catch those in that specific zone. I think the current system was a nice beginning, but it needs to be fleshed out more, with new items continually being added as possible furnishing catches.

Perfect Roe
Judging from the furnishing recipes and master writs, it seems like you are now treating the Perfect Roe as "yet another type of gold mat" for the provisioning skill line, much like gold tempers and Kutas. This is wrong. Mostly because the total server droprate for Roes is much smaller than for gold tempers and kutas. This is reflected in prices as well. Roes in PC/EU sell for 11k, Alloys for 7k, Rosin/Wax at around 4-5k and Kutas around 4k as well.
I suggest either increasing the droprate of Roes somewhat, or decreasing the amount of Roes needed in various recipes. Currently, using Roes in Citrus fillet and Orzorga's Bear Haunch only provides a very small advantage over using the vastly cheaper purple recipes instead. This is bad game design. Also, there are so many provisioning furnishing recipes that call for Roes where it doesn't even make sense. Mammoth cheese, botttled plants, skull goblet, and even the mortar and pestle! You could easily have made these use Frost Mirriam/Bervez juice and various amounts of other ingredients, just like alchemy utilizes various ingredients in their recipes, since there is no gold material to call for.
I feel like Roes should be reserved for the Ambrosia (unique ingredient for a unique effect), perhaps 1-2 provisioning recipes (that have to be unique, not just a little bit more resources than the similar purple one), and perhaps 1-2 furnishing recipes where it also makes sense. Not a mortar and pestle.
Currently we also only have common white fish and golden Perfect Roe as provisioning ingredients from fishing. You could easily add some more, in various rarity tiers from blue to purple.

Skill line and Fishing Rods
My final suggestion is also the one that would require the most work, but perhaps would provide the most investment into fishing as a minigame. I suggest adding an antire new skill line for fishing, like the other crafting skills have theirs. We currently have so many skill points available in the game, that I think there is room for another skillline. It should be only passives, like TG/DB, and the various passives could relate to something like:
- Higher chance of catching trophy fish/furnishings
- Higher chance of getting a Perfect Roe when fileting
- Shorten the waiting time between catches
- If you introduce a minigame when you have thrown your line, a passive to reduce the difficulty of said minigame
- A small chance to get 2 drops instead of 1 when you reel in your line
- A chance to see how many "drops" are left in a hole when you throw your line into it
- Passives related to being able to craft and/or improve your fishing rods
- etc etc

As for fishing rods, I suggest adding them as a new kind of item you equip as a weapon, with a very low damage, like the broom from the Crown Store. You could introduce a tier of 1-5 different fishing rods with different looks. Crafted through your passives in the fishing skill line from various wooden materials we have in the game. They could have X uses before they expire/break down, and you have to craft a new one, or you need to repair the old one at a crafting station.
Using a crafted fishing rod instead of a default one, would again increase your chances at various drops. One could increase your chance for furnishing drops, one for tropy fish, one for white fish. Or one could get better drops in foul water, one better drops in lake water etc. So you had better chances when you used a specific rod in a specific type of water, or you could pull out a specific rod when you wanted to fish for trophy fish, another rod when you wanted to fish for common whites and so on. Having them as consumables with X times of use, or requiring repair after X times of use, would provide a material sink as well, in order to get the benefits from the rods.

A fishing mechanic minigame when you have dropped your line, and/or a fishing skill line and fishing rod system would be the parts that require the most develoment from the dev team, but then again they would be the ones that make the fishing aspect much more interesting and engaging. The other parts about drops, lures/baits and such would be much more simple to implement.
I do hope someone at ZOS will catch the ball and that we will see a fishing update sometime in the future. I like fishing, and I find it something relaxing to do. However, currently I pretty much only fish to get my DLC achievements when a new DLC comes out, and then find other things to do after that, mostly because fishing is currently a very large time sink, with very little reward. You can do so many other things in the same amount of time that proves to be a better use of your time, in terms of rewards, plus it doesn't feel as mind numbly boring as fishing can do sometimes.
Anyway, that was my input, feel free to leave constructive feedback and maybe your own suggestions that I haven't thought of.

@ZOS_GinaBruno @ZOS_Chris