Actually, if it were up to me, I’d ban debates entirely. Too much is at stake to hang a primary nomination on a mis-statement or an unimpressive makeup job.
Or, for that matter, an uninformed, possibly even hostile, moderator.
A lot of candidates complain about not getting their message out. It doesn’t seem to occur to them that these 90-second driblets don’t constitute much of a message. Right now, about the only value I see to the debates is the marked increase in snark I notice in my tweetstream.