Wonderful! I love that you went away and thought about it.
As for system, I like the cards as in the BSG boardgame. For those that haven't played it - cards have "Human" or "Cylon" on them and get dealt face down at the start. You know if you're a cylon or human at the start. Everyone appears to be on the same side but you know someone might not be. Halfway through the game, a new set of cards are dealt, where people can become Cylons then. It's a great mechanic.
As for task resolution, I think someone really simple such as FATE, Fudge, 5x5 or even better (thinking while I type) you could refashion Warrior, Rogue and Mage into the digital world. Something like: Flops, RAM and Bandwidth. Flops (floating point operations per second) is your strength, RAM is the amount of skills you can have and Bandwidth the amount you do a turn. You balance your points betwen those - so you can be really effective (high strength) and focussed in being good at a couple of things (high RAM) but then you'd not be able to do a lot in a turn (low bandwidth).
Or something like that.
Or use the shared dice mechanic that I use in Cloudship Atlantis. That then gives the betrayal characters an opportunity to use up dice in the pool, making it difficult for the rest of the team!
Events could easily be done with a random roll table for the GM (cheaper/easier). Also easier for the GM to add more in. I think the final goal should not reveal itself at the start but appear halfway through. That way, the players may need to change direction or ignore the event/encounter they're working on.
This is nuts. But I like it.