Are there SFF/ITX cases that fit this bill, or at the very least mATX towers?
There are some nice MATX towers coming out:Fractal Design Define MiniLian Li A04
Already out and with a lot of airflow and good reviews, but imho totally fugly:In Win Dragonslayer
Good airflow, limited height for CPU cooler:Silverstone Sugo SG03/04
MATX Cubes:Lian Li V35X
ITX Cube:Lian Li Q08 SPCR review
Gaming oriented ITX cubeish:Silverstone Sugo SG07 SPCR review
Another gaming oriented aluminum ITX cube, not out yet:Cubitek Mini Tank
Even smaller ITX, limited CPU cooler height and graphics card length:Lian Li Q11
MATX Desktops, somewhat limited CPU cooler height:Silver Stone GD05 SPCR review
.Lian Li C50
Have you considered using a test bench case?
No, and I won't. There's lots of good options out there. Benches are only good for benching.