help with some team variables?

okay so i've noticed mw2 sometimes doesn't do the best of jobs with teams... always seems to make the same teams every game, over and over again (this is for private lan play using iwnetserver)

so like cod4 i'd rather give players a choice, either choose or have the game autoassign randomly... would i use "ui_allow_teamchange 1"?

i also tried the "party_autoteams 0", it seems to be cheat protected... do i need to do something like sv_cheats 1? apparently that's write protected

finally what does party_teambased do?

any other suggestions? thanks