I think I've suggested this before in other leagues, but it was never adopted. All non-playoff teams go in the draft lottery, and each receive an equal weighting (or one that VERY slightly goes in favor of the better records). Make it beneficial for teams to win as many games as they can. The waiver wires and trade opportunities are deep enough in these leagues rebuilding teams aren't completely screwed if they don't get the top few picks.
If regular season records were used instead, that at least prevents the tanking in the playoffs.