I would start with at least a trio of the shelldwellers. A larger group would ensure a better mix of the sexes.
For the calvus a pair would be ideal, although a single fish would be fine as well. They are opportunistic predators that may pose problems when it comes to fry. The brevis or occelatus should be fine with calvus, as would other larger shelldwellers. I would be more hesitant to put them with multifasciatus though.
The leliupi would also work best as a pair or a small group of juveniles, maybe 5-6 to find a true pair. They are generally a solitary species but broods have been known to peacefully coexist with previous generations. Julidochromis would fit nicely in place of the leliupi and care is virtually the same.
Edit: I keep saying leliupi...I mean leleupi :wall: