I remember PTB being the best team balance plug-in out there, but that was years and years ago. I'm sure there's something equivalent out there. Probably find something on the alliedmods forums.

When it comes to team balancing, it's all about competition right? Why would you want to stay on a team with decent people while the other team has a bunch of shitties on it? That's boring. Wouldn't you rather have evenly matched teams (skill-wise)?