Nearly got this finished. Just got four of the bosses to go back and do the QTE events and two more ranked run throughs. Why they couldn't put checkpoint selects on each chapter i don't know. Its a real pain having to spend 40 plus minutes going back to get to the bosses at the end.
One thing i have found for the beat Dad scores is playing through normal run through on medium with the Holy Chainsaw combo. Doing this way you kill it on the time + medals collected and even get enough points left over to allow you to continue once or twice (- 5000 points). Ranked is too much of a pain with failing the QTE and Mini Games sending you back to the start of the level.