Update: Pretty much all of these suggestions were implemented. Go Anet!
Because it will probably be a general overhaul of the game, instead of listing specific suggestions about Guild Wars 2 here, I've chosen to post general ideas and features that have made Guild Wars my game of choice. I hope all of these points transfer to Guild Wars 2.
Appearance vs. Functionality
I love that, eventually, all of the items and armor in Guild Wars have separated appearance from functionality. It's half the fun looking at armor and item skins to decide how you want to dress up your characters. It also keeps people guessing about your mods. Keep weapon and armor mods removable from their base items, so that an item bonus can be given to a skin that you would rather wear for astheic reasons.
On the same note, if the races in Guild Wars 2 provide some of their own inherent bonuses, don't make them inherently better at certain classes, and don't restrict certain classes to certain races. I want to be Charr healer and not automatically be outclassed by a race that's "better" at magic.
Healing and Support Classes
I main Monk, and I love support skills on other classes, like Expel Hexes and Foul Feast. Guild Wars makes playing the "healer" so much more in-depth and exciting than all other MMOs, who seem to be stuck on the pattern of:
- Cast buffs before battle.
- Spam the Heal spell during battle.
- Repeat (BORING!)
Keep the Monk-like class in Guild Wars 2 fun!
Free to Play and Microtransactions
It was already stated that Guild Wars 2 will continue the current Guild Wars business model of free to play forever. Bravo. On a side note about microtransactions on the Guild Wars In-Game Store, assuming something similar moves to Guild Wars 2, keep them balanced. It's fine to charge for character renames and appearance changes, as those are completely optional purchases, but don't sell anything in the store that gives anyone an advantage, like elite weapon mods or whatnot. People with more real-world cash should not be better at the game.
Zero Grind for PvP Play
Sure, Guild Wars has grind, but acquiring titles is completely optional and you chose to spend your time that way. When I complete the main quest in the PvE campaign or whatnot in Guild Wars 2, I should be automatically ready to PvP with the best items, gear mods, and skills. Players that play more hours should not be rewarded with a PvP advantage by the game. Grinding for elite weapon or armor mods is stupid.
The Guild Wars client has a simple hard disk directory structure, as well as low system requirements. It also correctly obeys ALT-TAB behavior on Windows, plays nice while minimized, and loses little performance while running in a window. The GW2 client should so the same.