Going to share few thoughts that are on my mind , see what you guys think about them.

1. I Would really like a system where Soul gems don't require PvE
-Make them selable for AP ( and only usable in cyrodil to not interfere with PvE content )
-Put some gold reward inside the PvP undiscovered boxes you get , or just put gems as reward from them ( 1 gem per box should be good enought )
-Give at the end of the campaign some kind of Cyrodil Soul Gem that can be used only there with infinitive uses to top10-20 players at the end of the race. ( I dont think people like gold rewards for participating in cyrodil , neither do it fom them , so some special reward would be more than welcome )

2.The whole crafting may be liked by some and unliked by others.
-If you can use Food/Pots and other things that can give you an edge over the enemies in PvP i don't think you should be force to get them only by crafting ( or buying from crafters ) Putting them for AP sales will be more than welcome aswell
-Disable pots and foods in cyrodil can also work , just to mention

3.The AoE damage and cap
- If there is cap 6 , i dont think there should be some abilities , like barrier effecting 20. I would rather have it at 6 too , to balance things out ( same goes for war horn , manuevers etc ) However i support no cap for aoe at all ( if you stay in aoe you deserve to die )
- damage done behind walls/structures etc should not exist. Some spells ( talons example ) and oils can hit behind wall bypassing LoS rules.

4. The Unbreakable CC's need to get fixed , not much to discuss on that one most of the people that spend good time in Cyrodil know that when you get stun/kb + root you cannot break out of CC. Vampire feed from sneak aswell

5.Balacing Skills should be always top priority , thats what made the first Guild Wars game last for so long , because you had lots of lots of options to choose from.
- Make skills that are hardly used , more suitable for use , either change their action or improve them
- Fix skills that do not work the way they should
- Also i want to say i support some other opinion that Unstoppable should require 5 pieces of Heavy and the same rule for medium/light armor skills

6. Camps , they should always work , and do have some kind of cooldown , team/group only camps would be great too , so randoms dont pop.

7. Mercs should not even exist , delete them from the game , had enought of them after i spend 5 hours killing waves of 20..20..20..20..20. Cyrodil should be more about PvP than NPC's.

8. Racial Bonuses needs to change somehow , else some races have really big advantage in PvP over others ( For example Dark Elfs with their fire resist/dmg bonus are one of the top races for Cyrodil )

Alright kinda tired , can keep going more , but i think its enought for now Good Night