As far as themes go, i dont really have a preference, but i can play all the possible themes, space, sci fi, fantasy, . . . they're all good.
I assume that guilds are like clans or squads in FPSs,so as far as they go, i normally like to stick to myself for a week or so, learn the ropes, then squad up with some randoms to get the squad play experience, then decide if i want to go serious with a guild or not.
I dont think guilds would be real good for me. In the FPS's im a big squad memeber but sometimes ya just want to have some fun and cause some destruction by yourself, do your own thing so to speak
As far as time goes, at the moment i have all the time in the world, (suspended from work

but still getting paid

) but in the next month or so things will change and i'll probably be back to a couple of hours a week, (if it can overpower my 2142 urges)