First off let me introduce myself: I am a hard core gamer who started MMOs when Everquest came out. I have tried many mmos, and I have likely missed a couple great ones entirely. Guild Wars 2 seems like an mmo with a lot of potential, but feels very unfinished in many areas. So without further ado, here are my suggestions for the two primary game modes:
PVE
Waypoints: scaling in cost as you level is somewhat understandable, but it is a little too much cost imo.
Exploring: The rewards are nice for fully completing a map, but I think it should have some impact on waypoint travel.
Renown hearts: There should be an option to redo/re-complete renown hearts (with the restriction that the map has to be completed first and you can only do them once every few minutes or something). Some have neat events that you cannot enter once you complete the heart. Also this would encourage players to return to areas to complete them with their friends (even if it was just for currency).
Difficulty: Based on what I hear dungeons are super hard, and normal pve just seems like a boring grind. I would prefer pve be a little more difficult in more areas, with greater rewards to compensate.
Dungeons: Currently I have yet to get into a dungeon group. It seems the way to do this is go to the zone and advertise, but I am also a necro, which seems to be a basis for not inviting me as well. A dungeon finder/auto grouper would be nice, or a world wide lfg function (there may be one of these but no one uses it). The fact is dungeons are usually passed over by many players because the rewards are not worth it and they are very difficult (not saying make it easier, but make the rewards match the difficulty to make them more appealing).
Events: Once you get out of the starting zones these seem few and far between. I would love to see more pop up in the higher level areas.
Pvp
Groups: It is difficult to group with friends and enjoy pvp. I know it would be imbalanced to allow large groups to queue for solo pvp, but you should at least be able to group with a couple friends and queue. We want to play with our friends, but pvp does not offer many options for that.
Formats: The formats seem very limited for small-scale pvp atm. You have capture and hold points and… wait that’s it. What about 2v2 or 5v5 death-matches (each player is eliminated as they are defeated unless revived by an ability or some well coordinated cc, no re-spawning). Capture the flag is a time tested classic for pvp as well, and dueling (many people have suggested these options from what I am reading). If I could have one it would be the death-matches though, I love that kind of combat where last man/team standing wins.
Balance: I realize a lot of data is still being collected here. However, a few things should be quickly evident. Pistol whip does a little too much damage, and chain cc by a single class should be more limited than what it is currently (looking at hammer warriors mainly…).
Rankings: Yeah the armor rewards are neat, but there are not many ways to distinguish yourself in pvp. What about a leader-board or titles based on ranks/tourneys won. Pvpers love a way to gauge their skill versus others.