I have one that will cut-down on my excessive game purchasing. If I can stick to it is another story, but I think I can.
I'm only gonna back/buy games that are specifically for 1 Player only, 1-2 Players, and a few for 2 Players only. I realize I'll be missing-out on many excellent 1-4+ Player games, but I have several nice multi-player games already (Dune Imperium, Lost Ruins of Arnak, etc.). Since a lot less low player-count games are released (War Games notwithstanding), I think this strategy can help me.
So far, my recent (and not too long ago) backs and buys have been (in no particular order):