One metric that I have not seen anywhere is the record of teams in or under consideration for the tourney vs other teams in or under consideration for the tourney. In the end, these are the teams that will be facing each other. Who cares if you can beat Marshall if they have no chance at the tourney. Wichita State has a nice RPI but you won't have to beat them either. Obviously, this cannot be used as a stand alone measure for either seeding or inclusion, but I believe the committee has this at its disposal and it would seem like an important criteria.
I did a quick analysis of this and the results are below. Teams included in the metric are 1) the obvious locks, 2) any remaining RPI Top 50 teams, 3) the bottom 18 automatic bids for one-bid conferences (if the conference tourney is not complete, the #1 seed is used) and 4) all other teams widely considered to still be under consideration (Nebraska I feel vacated that list today, so Baylor and New Mexico are my last inclusions on this list).
A few observations...1) Michigan, widely scrutinized on the message board for zero "quality" wins, has beaten 7 teams meeting this criteria, more than Xavier, Cincinnati and Texas A&M. 2) USC may be closer to the field than people think. Yes they have bad losses, and quite a few of them, but a 6-5 record against this list is not too shabby. 3) Richmond may be in more trouble than I thought. The win over Purdue is probably enough, but they could use a victory over Temple just to be sure. 4) If Alabama plays and beats Georgia, the Tide will be 4-4 and the Dogs 4-11 against this list. I would lean toward 'Bama, especially with their season sweep of Georgia.