If we play Indy in the divisionals or AFCCG, we would still be at home for that, so we could have 2 home games regardless. Heck, I think we could conceivably host 3 games, if 6 and 7 upset 3 and 2, respectively, and 7 then goes on to upset 1.
So, correct me if I am wrong, the optimal situation would the number 4 Bills beating number 5 New England in the WC, then hosting the number 6 Colts or Raiders in the divisionals, then hosting the number 7 Colts or Chargers in the AFCCG. This assumes Patriots, Chiefs, and Bengals wins and the Steelers not getting into the post-season, all of which are very likely (well, except maybe the Patriots beating Miami).