The 4 types if MUD players
mud.co.uk
mud.co.uk
I'm an ESKA, which has always left me in that odd group of players who has never been satisfied by the core mechanics any MMOG. Most MMOGs cater to As, with a bit of S and K. The Es seem to be mostly ignored, perhaps because they'll never be satisfied by your standard World of Warcraft-copycat grindfest.
There have been a few MMOGs that would have appealed to us E___'ers, SWG in its original form was basically a E___'ers wet dream, especially if they'd continued to expand the number of planets over time, rather than focusing on poor theme parks.
Neocron has a fair bit of E___ appeal too, as does Ryzom. Anarchy Online also has positive features for us (and was the first MMOG I paid a lot of attention to, so it's the one I keep going back to...), but lacks a lot of the deep crafting system that a lot of us E___ers desire.
There's a common thread to those games, they're all pretty much 'sandbox' MMOGs, games where you're not pushed into a specific chain of events, nor pushed into PvP as a necessity (god, I hate the vocal K___'ers, they insist on ruining every MMOG they touch).
Anarchy Online and Earth and Beyond were mildly interesting, but that's about it.
I don't think PvP-as-a-necessity is inherently bad in a sandbox exploration game. If anything, it's good: other players will always be more interesting to compete against, whether by direct combat, economic competition, or diplomacy, than AI NPCs. IMO the only way to get a sustainable game that consistently produces interesting content is to rely on the players.
In my experience the primary aversion to PvP comes from games that weren't designed from the ground up to be about PvP, but had it forced into the system in a way that was simply not enjoyable or interesting.
EVE Online was "so close, yet so far" to this ideal, in that it got a lot of things very right but designed the economy too much around grind and spent the past few years focusing too heavily on strategic combat with capital ships instead of individual players.
Nothing beats the exploration and interaction value of an expansive world (say, something like Exalted), a custom story written for your character, and a group of people who come to spend time doing nothing but exploring and interacting with and generating it. Anything driven by bits is a shabby and distant second best.
Though if you must, something like Nethack can keep your E side happy for a while.