We already have a centrist party. They're called Democrats.
Maybe centrist according to your rather out there PM scores, but not compared to the American people.
I'm pretty sure a generic Democrat is closer to your PM score than a generic Republican is.
I've seen zero positive fiscal scores from Dems on this forum and, given how simplistic our test really is, I highly doubt any Senate Democrat has a positive one either.
Key phrase. Atlas is hardly representative of the real world. And even if you assume a generic Democrat has a negative economic score, it would still probably be closer to yours on balance than a generic Republican's would be.