Currently area51 is overrun by proposals and questions that are sometimes not of very high quality. I think the problem is, many are addicted to the rep-system (I won't even exclude myself) and therefore try to ask as many "good" questions as possible even on proposals they are not following. As a result there are too many questions to be judged with just 5+5 votes.
I make the numbers up, but basically:
I propose posing questions costs 5 rep which will be refunded as soon as 5 votes prove its usefulness (may also be mixed e.g. 3 on-topic 2 off-topic votes) and be rewarded with 10 rep as soon as the on/off-topic-status is determined. Voting for questions for a followed proposal should gain 1 rep per vote, maybe 2 rep if the question has less then 10 votes or is not clearly on-/off-topic yet¹. The amount of proposals that can be followed should also be limited (or at least how many can be joined per week).
¹ the latter might cause people to vote in such way that already clear questions become instable, so some anti-seesaw-mechanism would need be made up,too
edit (thx Arlen) Some way to gain much rep has to be provided to relieve the moderators, as Arlen pointed out. So 5 rep points per vote despite the question already being clear in its topic-ness should be needed. And maybe multiplying all rep-#s by 10. Of course this whole suggestion requires the voting limit to be relieved, plus it'd make the meh-vote obsolete (everyone disagreeing with the question could ignore it knowing the poser has -5 rep for that)