Cacophony, RiceKrispies, and I discussed this some on irc and threw up these ideas:
1) More ppl advance from the winning team than the losing team
Ex: if we start with 12v12, 10 advance from winning, 8 from losing, etc.
2) Use mainly tc and cp maps; threw up the ideas to use hydro, well, granary, and I proposed ctf_turbine_v3 if we need to use a ctf map, due to its small size