I agree lists might tempt BP's to collude among themselves.
"Put us in yours and we'll put you in ours" type arrangements could easily be done.

I believe token holders have enough criteria to discern by themselves why and who to put in their chosen BP's voting list, without providing them with a pre-cooked list of candidates.

That's why a good set of guidelines for token holders to follow when preparing their voting lists is a better and more respectful approach.