I like 1..3 above. I don't like 4, not because it's not a good idea, but because I suspect it would be a DB hog, just like the Node Navigator nodelet. (If there are any DB-heads with some free time, I'd love to get it back.)

Some additional ideas: Rate-limit how many nodes can be considered by a single person per day, or for that matter, how many considerations you can vote on.

Take away XP for poor considerations, and possibly give points for ones that succeed. (Requires more editoral work, though.)

Hide the name of the consider to voters.

Record the names of voters on reaped nodes.

Give editors a check-box that says "vote this option three times" on consideration voting, and take away editoral deletion.

Change the required votes for reaping to 2*(keep+edit)<reap

Allow editors to unreap nodes.

I'm just brainstorming here, of course...