I got to say GW2 is an interesting game for me. I really enjoy it but at the same time there's some features I really hate!
The open world feeling
The character creation
The fact your level adjusts to zone
The art style
The removal of competition for nodes/mobs
The incentive to help others and group
The lack of story
The lack of alternative activities (it's either quest, pvp or explore)
Only having 5 character slots (alt-aholihic)
The fact you can't change your email without having a list of information (including a bloody invoice)
That Warriors get a long distance rifle whilst Engineers have short range (surely it would make more sense the other way round)
Shared bank rather than being able to mail alts
That dye isn't account bound
The profession system
The Black Lion Trading Company especially! I don't mind some of the payed items BUT extra bank space, character slots and exp boosts seems ridiculous.