Cleaners will do fine with peps. I've had cleaners, blood red, peps, and a pair of CBS - oh yeah, and a pistol shrimp. in a 72g. Maybe I was lucky since there seemingly was no agression issues. Everybody had their own space.
I'd consider a yellow tang or a yellow eyed kole. Do the yellow tang last though IMO
. Some can be kinda agressive on newcomers. Althoug most say the purple can get to big for a 75g, I have a medium sized one that isn't growing fast at all and really is at peace being the largest fish in my.
Try a blenny. Midas is my favorite. How about 3 blue green chromis? Also consider a pistol shrimp and goby combination. Just make sure your rocks are firmly planted on the bottom so the pistol's tunelling doesn't cause an avalanche.