I would love to see a wardrobe system introduced in game, so all those high end armor/weapon skins can be saved and viewed, rather than have them take all my bank space, also being able to preview armor/weapons I have not collected yet would be awesome, this way I know what I want to work towards.
Separate storage for crafting materials would be wonderful, as there are so many surely another tab in your bank for them would be easy enough to add (gw2 does this well), and the ability to send crafting mats direct to the bank from anywhere in the world, as there is nothing worse than having to travel all the way back when in the middle of a quest.
I know some hardcore fans won't like this but I am a little ocd when it comes to collecting, and the thought of running past all those items and not collecting them, just makes me shudder.
These little things would just make life a little easier in game.
I'm not comparing games either btw, as both have their pros and cons, i'm just hoping that if enough people want to see this maybe, just maybe a dev will read the post and put the idea forward. Who knows.