I think we can take it on a thread by thread basis without too much issue.

For major issues I'd think maybe 8-10 votes total at the moment

Having weighted votes seems to me too complicated to do well. Some problems are when there are many votes (unlikely to really happen here). and the other is that the scales here wouldn't correctly represent the true vote value. For issues were weight would be a factor just limit the poll to one vote.

As for the time limits I agree with you, we ought to have deadlines but if we don't feel there has been enough activity on the vote to go through, extend it or take it down and rework it. Perhaps removing the options no one voted for or a complete overhaul of the idea and question behind the vote.