On Interaction (or Pride)
Ultima Online is potentially the greatest MMO out there; the level of interaction possible in UO is above and beyond what I've seen in other mainstream massives.
In UO, the developers truly have the ability to make it an interactive world. The story can be directly influenced by player actions during quests, and there is the possibility of adding new structures, creatures, and so forth, without the need to commit art resources to world building. In fact, the whole idea behind UO would seem to indicate that this was the intention: Upon the shattering of the gem of immortality, each copy of the world contained in each shard was supposed to diverge on it's own path, kinda like the idea of parallel worlds. Each shard would have had it's own unique culture. To some degree this did actually work, there was for some time a volunteer program where the event/fiction folks, called Seers or Elders, were capable of propelling a shard's unique flavor. Lately, to my knowledge, there's now just the primary storyline, each shard getting a slightly flavored version of the same events.
Ultima Online's greatest strength, from a story standpoint, is it's ability to adapt and change according to what the players do. This really should be exploited as much as possible. In a world like UO, I think one of the greatest ways to retain subscribers (by way of increased player involvement) is to really let your players feel like they've helped shape the world.
On the world-shaping point, I've often felt that players should be able to make a more profound contribution to the UO world; an example of this might be a monthly writing contest for in-game books, where the top few entries might be added to the books that spawn in libraries across the world. You'd have to submit the forms via web, and check a box to allow your work to be published in game (with all legal mumbo jumbo involved), and the writer might even have a say in what shards his or her work can appear on.
On Accomplishments (be they good or evil)
I think a lot of work could be done to really allow people's characters to feel more heroic/evil (which is a whole other post entirely). You don't really feel like a hero when you escort some geezer to a fishing pier. I'm all for the little quests where you help out NPCs, but I think the really cool stuff lies where you can really get involved in a quest, trying to follow the path of a virtue - or antivirtue. Imagine your PVP players being Knights of the anti-principles: Valai, Knight of Hatred. Or, perhaps, deciples of the Shadowlords, who embody the anti-principles. Perhaps you would quest to gain the title "Child of Faulinei" or "Knight of Falsehood." Mind you, Knight of Cowardice doesn't really sound so hot, but hey, someone might dig that.
UO has great potential for players to play both evil and good roles, and the evil side would seem to be neglected - you don't see Lady Minax sending out a global message to all those with negative karma to meet her somewhere to plan a raid on the good guys. It's silly to assume that everyone wants to be a hero - being the bad guy is one of the things that make some games great (take Fallout for example, and selling your wife into slavery).
On Skill Gain (making 99999 plate arms = boring)
The skill gains in UO are, simply put, boring and repetitive. In absence of a leveling system (don't get me wrong, I prefer skill-based vs. level-based), it would appear that UO's skill gains are intentionally boring. Sure, you can craft items to order as a blacksmith, but no one wants your goods until you're maxed out (and sometimes not even then). There really needs to be some investigation into why it's necessary to force players to do this kind of repetitive chore - it's given rise to automation programs that are more interesting to code in and optimize than doing the actual skill gain itself.
On Items and Equipment (they're PANTS, why can't I wear them?)
As much as race-dependant stuff can be cool, it's generally not cool to players if you restrict what they can and can't use in an item-based game. There are robes and pants in Ultima Online, for example, that can only be used by elves. Why? What logical reason could there be for a simple tailored item like a robe to only be usable by an elf? Does the fabric hate humans? Things like this really only frustrate players. If there's a good reason for it, sure, but not just because you need something to differentiate the player races. Enchanted elven longbow? Sure. Elven pants? That's just stupid. Same goes for armor only wearable by females: Did it ever occur to you that some (really strange) males might WANT to wear that female plate? Not that I'm encouraging this, but there's no real reason not to allow it, unless you're afraid of lawsuits from parents of boys who suddenly start wearing bustiers.
Aaaanyway, I'm mulling a UO storyline around in my head, probably won't be done by tomorrow. Monday's my "deadline," so we'll see how that goes.
I have more thoughts on the state of UO and what could be done to improve it, but I think I've done enough damage for one post, so, until next time, stay away from the studded bustiers!