BSG newbie - Baltar is irredeemable. Am I wrong?

Spoilers

Going into Season 3, Baltar has been collaborating with the enemy and has made numerous poor, treasonous decisions, in his sweaty and insecure manner. Why shouldn't this guy get tossed out an airlock? He's the most obviously weak character (weak of character) even if he's supposed to be a genius.
Genius of what? A slave to his appetites and lacking scruples and nerve? He stands out like a sore thumb as being afraid of every imagined consequence.
Yes, it makes the show interesting, but he's too far gone to be able to trust going ahead.