RNG - Random Number Generators (for goodies)
While this concept is a mechanic to distribute items from loot and chest drops in just about any game, but in Guild Wars 2 it's a core mechanic in just about every aspect of the game. From boxes, crates and keys you purchase in the cash shop (regardless if it's money or in game gold) to the mystic forge for all things Legendary, the dependence on this system is not only frustrating, but also very uncreative. Guild Wars 2 is not alone in this mechanic, but you would think, after all the complaints and general anger over it, it would simply go away. It adds nothing to the game and arguably caters to the gambler in all of us, pumping more money ANets way.
DR - Diminishing Returns (the anti-farming code)
I get it, this is in the game to deter not only auto-bot farmer, but also to keep players from staying in one area killing the same stuff over and over for drops. The hope to have players play more of the content, occupy more of the game, is lost on ANets design team i think. The best possible way to do what this is to have the entire game be rewarding, sure people will go and farm tier 6 materials, but they should really have that option, farmers are gonna farm. This not to mention the stacks of these artificially rare materials that are required to get the good (pretty, sparkly, shiny) gear. Seriously, there is a far better way to tackle these "problems", but it requires extra effort. Lord knows people are paying for it through the cash shop, maybe they need to add a second shift...
Oh, where is the Guild in Guild Wars 2?
This really irks me to no end. They add these new guild mission yet don't address what i would think is a simple issue, knowing your roster. When did this person last login? Who knows... What's their home server? No idea... This not to mention lack of GvG or Guild Halls, there's very little Guild Wars in the game. I understand the lore, but yet it's practically vacant from the story telling, leaving players to wonder, just WTF Guild Wars even means, there is no actual war between them at all. Mine as well call it Grind Wars, least that would make more sense.
Crafting is dead - Give us a reason to craft and let PVE WVW players re-trait easier (cheaper)
Most crafting professions are basically a quick leveling tool and after that are practically useless. This idea should fall under some other category, but let crafters re-trait their gear already. Why are PVE and WVW players so heavily penalized when they decide to re-trait? There's so many things they could do with crafting, is just boggles my mind as to why it's so utterly horrible to be a crafter in most cases. What happened to the Guild Wars way of stating gear? Do you guys (the dev team) like managing more gear stat types? We certainly don't enjoy scrolling through lists of different gear types... just give us an insignia system that will re-stat our gear and be done with this non-sense. Ditch all these different stated gear at the vendors, such a waste of resources, it's actually pathetic.
This next little tidbit falls under the "spread people out" category. Give us interesting ways to acquire new recipes and have them zone themed. If my toon is a professional crafter, why can't i craft any gear i want? Give me a recipe to craft CoF gear or some spiffy sparkling weapon, so much you could do here. Let's not even get into the fact that the Mystic Toilet is such a central focus for crafting, taking any real value from crafting away.
Blow up my video! Optimization
Forget what you know about gaming in general, the Guild Wars 2 engine is in some weird twilight zone of engines. I've got a pretty beefy machine and the game still becomes a slideshow in large battles. The culling removal was nice, sure, but for some reason it's so punishing to my processor (an 8 core btw), that playing in larger battles really "grinds my gears" and makes my machine cry. I won't go into the absolutely vacant support system for the mac client, but good lord i'm glad i have a windows machine and don't play on my mac.
Communication is key
All i have to say here is get some people to handle the forums, period. Hire some freelancers. I know plenty of people willing to take 4 hours a night to get on the forums and post official responses and give players the inkling of hope that anet is listening to them. This not to mention, get a canned piece of forum software for goodness sake. This custom forum thing has got to be killing the web team, since it sure as hell is killing us. It's so bad that i could actually suggest phpBB and say it's about 15 years better than what you guys are running. Invision Power Board is an amazingly strong, heavily supported piece of software, I can only imagine how much cash you guys would save just moving to that and ditching this custom crap.