I think the only feasible way is to shorten the LCS to 5 games and keep everything else intact. The play-in game earned a lot of buzz from people, and revenue, so it's not going away until Selig leaves the post. The postseason is too long. The casual fan seems to move on from baseball after the middle of October, especially if the local team is out of it.
I, personally, would shorten the regular season to 145 games. But we all know that owners will never unilaterally go for it. They will also never return to two divisions per league, even if that is the best way to maintain excitement and get the best postseason teams.