These are big questions, and you can get incredibly detailed answers online very easily. But I'll give you some short answers.

1)There are "big" and "small" armor pieces. Big pieces get the full bonus of the enchantment, on small pieces you get half the bonus. This is the reason "infused" is bad on small pieces. 'Big' pieces are head, chest and legs, and the rest are small.

2) broadly, unique items are the same as regular set items (but are easier to farm for). There are a couple of exceptions in certain sets that have traits or enchantments not otherwise available (the trainee set is the best example). Obviously the weapons from maelstrom arena and dragonstar arena are better than regular gear, if you count them as unique.

3) healers and tanks can do better with other traits, but for dps the best are almost always sharpened weapons and divines armor. The reason is these increase dps better than any other, and there are fantastic threads from maths super brains that show this convincingly. If you do pvp then you will want some pieces in impenetrable to counter crit.

P.S. this is simple advice, and what is best for you will depend entirely on your build.

P.p.s. while having gold gear is nice and better, it is most noticeable on weapons, so many (most?) Players don't have gold armour but do have gold weapons.

AdamBourke wrote: »

1) How do enchantments apply differently to different pieces of armour? I know the part-type affects the enchantment strength, but would say, magicka enchantments work better on the light armour? Or any other things like this?

As @Jim_Pipp mentioned, the big pieces are head, chest, and legs. Some players like to have the Infused armor trait to further boost the enchantment effect on these pieces. Most people don't bother with infused traits on any of the other armor pieces because the bonus is a percentage so the overall gain is small except for on the big pieces.

It's really a balancing act between attribute points, gear set bonuses, armor enchants, and champion points. I tend to select the gear sets I want, get the armor and put it on. Then I enchant the armor with stamina for my stamina DPS builds, magicka for my magicka DPS builds and healers, and health for my tanks. I look at my numbers and then decide what kind of food or drink I'll be using to resolve any deficiencies.

Next, I spend my attribute points to get my health to 18k for DPS and healers or 30k for tanks. I believe it is most efficient to get your health from attribute points, so try to get the amount of health you want that way. Then I spend the rest of my attribute points in magicka for magicka DPS builds and healers, or stamina for stamina DPS builds and tanks. At the very end I decide how to enchant my jewelry.

As for weapon enchants, support classes that don't do much damage typically use either resource management like Glyph of Absorb Magicka or Glyph of Absorb Stamina or enemy debuff enchants like Glyph of Weakening or Glyph of Crushing. Damage classes tend to either use poisons or a straight damage enchant like Glyph of Flame or sometimes Glyph of Weapon Damage for an occasional short boost in damage.

AdamBourke wrote: »

2) Are unique items any better? I'm planning on crafting my armour and weapons, but I will need dropped jewellery. So would a dropped unique piece be any better that a dropped piece of the same set?

I've noticed the unique pieces often have specific and limited traits. For example, if the jewelry for a tanking set have the Healthy Jewelry Trait on them, then there might be a unique neck for that set that say, has Stamina on it instead. Of course the details vary widely across all of the many sets in the game. I really like the Armor Sets page on the Fextralife website for looking up set information.

AdamBourke wrote: »

3) Traits... I hear that some are used more than others... sharpened seems popular - but which ones are the best, and whats wrong with the other traits?

One strategy is to use the Infused weapon trait with either Glyph of Weakening or Glyph of Crushing to make the debuff stronger and apply it more frequently. Of course the Powered weapon trait is great for healers or maybe even a health stealing nightblade tank. The Sharpened weapon trait is great for cutting through armor on some dungeon bosses but especially players in Cyrodil. The only weapon trait that nobody really wants is Training. While people do craft full sets of training armor to power-level their characters, nobody really wants it on a set item weapon.

I hope this gives you some insights on how to proceed. Let me know if you have any questions!

And don't rush into golding.. I often go through quite a few different purple sets before settling on a combination I like. Spending a fortune on golding a full build to find that either it doesn't perform or you don't like the way it plays would be a disaster. Besides, aside from weapons, the difference it makes is minimal - so if its not working for you at purple, it won't work for gold either.