4 Wheel Disc Problem

[ixfn]

I'm guessing the line to the rear was 1/4" for the drum, I would consider changing that to 3/16". I'm stumped by the pedal travel issue; is the action firm or loose (though you said it didn't feel like air) when depressing the pedal? I agree that you should verify line pressure at the rear calipers (SSBC makes a nice kit), or consider plugging the rear port to see how that affects pedal feel to get a diagnostic starting point.