what do you like is my first question!
you have to work with aggressions.
like mixing kenyi, johanni, zebras, auratus. they are a great mix as they are so mean but work together. i adore zebras personally so they are reccomended!
or peacocks, venustus, labs, bumblebees. they are gentler and look stunning. the peacocks + venustus arent mbuna but are stunning in colours!
for a 72, maybe about 30 fish. its a lot, but overstocking helps big time with aggression.