OHG. When I said you weren't getting good stocking advice -- well, that was an understatement!!!
First, you have mixed Old World (mbuna) with New World (convicts), which is a poor idea. They have different water needs and just in general a different "language." If you want an African tank, then, yes, remove the convicts. (I'm assuming you have the right water parameters for Africans or are willing to buffer the water to achieve it.)
You then have three of the most aggressive cichlids there are: the kenyi, the auratus and the johanni. I don't personally do aggressive mbuna tanks, so I'm going to give more general advice here. You need to do significantly more research on your African species and then decide which (if any) of these you want to keep. You also need to stock either an all male tank (not generally easy to do with mbuna, but a great idea with peacocks/haps) or you need to stock multiple females per male with only a few species in one tank (due to aggressionand interbreeding).
So this gets back to what are you trying to achieve with your tank? It's large enough to do a great all male peacock/hap show tank. Or you could easily do some sort of breeding set-up, or even a less aggressive mbuna tank centered around yellow labs, p. acei and ideotropheus sprengere (rusties).
Glad to see the nitrites are going down!
