I've noted below a few features that I think could improve quality of life for players. None of them are asking for fundamental changes in the game:
1) Reporting gold sellers. Although I understand the need to fill in details when reporting a player for breaking the rules, I don't see the need to do this for reporting something as wide spread and simple to understand as gold selling. I would like to be able to just right click the name and report for gold selling with nothing else needing doing. As it is, it takes me enough time to fill out the report that I often can't be bothered if there are multiple gold sellers at once.
I would also like reporting a player to automatically add them to my ignore list. Bit of a ball-ache to report a name for gold selling and still have that advertising filling up my chat-box until I also ignore them (which at least doesn't take as long).
2) Filters. I'd like to be able to filter bank content, not just by type, but specific profession in the case of trade materials. I understand that some are used in several of them (race and trait stones), but most are not. It would save me considerable time when moving things around to have a filter to show me only provisioning or enchanting materials for example.
3) Ability to see account inventories. This is the least likely to be granted I suppose, as I imagine it helps fewer people. But it would be useful to me as a crafter to be able to see what items I have on my alts without having to log into them all to find that thing I know I have but just don't remember where. I'm not suggesting I should be able to craft from the other inventories in the same way as I can from the bank (awesome feature btw, thank you), but just see it.
4) When in the deconstruct window, it would be helpful to be able to identify traits on items that I already know. Yes, I can keep flipping between the deconstruct and research window, but if I have a lot of items, it can take some time. Just a little message saying trait known or trait not known, and only needs to be when viewing the item in the deconstruct window, would be immensely helpful.