I finally got Master Angler!
But so this isn't just a "Yay, me!" thread, I want to share how fishing greatly improved my ESO experience.
I started fishing because it had some nice dye colors and because I could get perfect roe, which sold for a nice chunk of change. I told myself I was fishing for the achievements, not the perfect roe. Nevertheless, I got plenty of perfect roe as I fished my way through the zones and that formed the foundation of my current fortune in ESO. Its no exaggeration to say I'm a rich player (by the standards of an average player) because of fishing.
I was fine fishing in the base game zones, but Cyrodiil terrified me. I came to ESO from Skyrim, so I was a pure PVE "I'm-going-to-pretend-this-is-a-single-player-game" type player. But ZOS, those dirty rotten schemers, had the nerve to put fish in Cyrodiil. Fish I needed for Master Angler! So I gritted my teeth and jumped into PVP land.
I got my first kill because of fishing. I was EP and hanging out on the DC side of Lake Rurmare, fishing in the foul water there when I get jumped from behind by a DC vampire nightblade. I was on my Dunmer MagDK, and I'm pretty sure that vampiric weakness to fire was the only reason I won that fight, because I didn't know what I was doing. But I killed that nightblade with a lot of Burning Embers and went right back to fishing.
I also spent a lot of time sneaking around the AD back gate to get my ocean fish (Why, ZOS, why did you give AD all the ocean holes?!) then left Cyrodiil swearing never to return now that I had all my fish. But fishing in Cyrodiil infected my with the PVP bug and I kept coming back. Now I PVP with a guild regularly on PC/NA Vivec, something that would have never happened if I hadn't wanted those Cyrodiil fish enough to venture into PVP territory.
Fishing brought me to both a fortune and a whole new playstyle in PVP. Even though I'm "done" with base game fishing and glad to be done with certain zones (The Rift, I'm looking at you!), fishing really made a positive difference for me in ESO.
Credit where credit is due to these folks for lovely fishing maps, without whom I would have been substantially more frustrated:
http://teso-guides.com/the-elder-scrolls-online-maps#fishing_maps