The life structures you need to start would just be glider guns. The glider guns would fire into walls of "collector cells" which are not Conway Life entities, but are implemented by the game directly.
Likewise, the character is not a Conway Life entity, but implemented directly by the game.
I think that's going to be unplayably difficult for anyone except serious programmers
What I've envisioned might well be appreciated by Life enthusiasts.
To the extent that resource collection involves stuff happening in Life you will struggle to balance it, and to the extent that it doesn't it's not really life-based at all.
Obviously, because no MMOs have contrived mechanics, ever!
Seems to me Life has a lot of potential as abstract art, though. I'm almost curious enough about what they're doing in Second Life these days, to sign up and go have a look:
http://www.conwaylife.com/forums/viewtopic.php?f=7&t=2068#p2...