squishy brake pedal

Having to "pump up" the brakes to slow down is a classic symptom of a bad/worn master cylinder. I had a car that developed that exact problem (with those symptoms) once, and needless to say I had it repaired as soon as I could. It might be worthwhile to double-check that everything is fully bled.

I understand that these chassis have hydroboost brakes rather than vacuum assist brakes. Problems with the booster portion won't cause the problems you describe; they might very well cause limited braking power and strange pedal feel, but without improvement with the next pedal press.