So this is a post that has come from mainly myself but has had others add to it when generally talking in game. I think the game would benefit from any (hopefully all) of the features listed in this post. I'm fully aware that some of my suggestion could take a long time to come about, not be possible, or just not wanted in game. Here's my 2 cents anyway.
Okay so first things first, outside the game, but still in game...?
Resolution:I'd love to be able to play the game in 1920 x 1080. even if it's just i can see more of the map instead of black.
I think this would benefit the game. Not only will new players be able to play in proper full screen, but navigating the mazes will be a little easier as you'll be able to see further.
Enter to log inEvery day I log in, I type my name then tab type my password, then enter. every time I have to manually click the log in button. It's not a massive change, but it would be really nice to be able to enter to log in.
On to in game suggestions (short interlude)
Guild ChatHaving a guild at the moment, for me seems to have very little meaning. If we were able to talk as a guild, we could have maybe more of a faction feeling to the game. You could come up with arena strategies and new boss tactics as a small force. I think this in hand with guild forum pages would work really well.
CraftingAtulos has a huge variety of monsters, putting crafting in to the game could give them all something to drop. I'm sure a crafting system would go a long way to making more interesting, and it would give characters at cap (when they get there) something to do. Level a skill in crafting. crafting materials and recipes could be obtained from bosses (maybe on a small drop chance to make the item rare) and mission (for the more common recipes).
Trading (Contributed by others)Trading would give crafters an ideal way to make money/obtain crafted or bought weapons and share recipes. Personally i'd love to see more interaction between players, and I think this is a good way to do it.
Visible hp and Hit markersBeing able to see the enemies hp (and yours) and the damage done means that when you get a new weapon/level you can see that you hit for more, or you take less damage from something. It gives everyone physical numbers to work with, they can see the power increase and will keep them involved with their characters progression.
Further gear progression (Contributed by others(I think))I've heard a lot about having far more than enough money by the time you buy wrath gear, and a few people have millions of gold to do nothing with. Perhaps adding new weapons in for level 400/450/500 just so there is more progression than just your level. This could tie in nicely with crafting.
Specific Art for Weapons and ArmourI'd live to actually see the weapon i'm holding on my character, and the armor I have to protect myself with. Getting a weapon that looks more epic for each upgrade. - Not sure what you'd do with the reaper and orc skins

IMO I'd just be happy with that sythe.
Active Combat (Contributed by others)Having played MMO's with hot keys based combat (WOW, Rift, Guild wars) and more auto combat MMO's (Runescape) I really enjoy combat when it differs from class to class. Having iconic spells for each class really builds character distinction and game immersion.
I'd love to hear feedback on my suggestions, pros and cons. Be it community or Dev feedback. Let me know what you think.