Here's a more or less general description of Cyps, which touches on Paracyps, another interesting fish (don't let Malawi Cichlid page name confuse you, they're not a Malawi fish). Another
here. If you watch some videos, Cyps are active, generally mid level or higher, open water fish. "Jumbo cyps" can be @ 5 inches.
A compatible group with some pretty and interesting species is Altolamprologus, which are more rock oriented.
Male Benthochromis can be spectacular fish, especially in breeding color, also open water fish, get some size to them, but Benthos aren't always available, also expensive, and not the easiest to keep. Don't really know about keeping cyps and benthos together, both typically peaceful, but can't recall seeing it much, same water level and seems like people do one or the other.
A larger fish I have a lot of experience with, certainly worth considering in a large tank, are Cyphotilapia gibberosa, mine are kapampa. Not a good mix with Cyps, though, which they hunt in the wild. But people often keep them with Altolamps and sometimes Neolamps if you give the Neolamps rocks and caves for cover.
This hardly exhausts the possibilities for Tanganyikan cichlids, these are just some I'm more familiar with. An interesting type is Gnathochromis, kind of a Tanganyikan version of a Geophagus.
On the SA side, a combination I like a lot are Heros species (severums), some of which are pretty showy (notatus, rotkeil, severus and some others) and eartheaters (Geophagus and some others). Geos can also be really nice-- see altifrons, sveni, winemilleri, mirabilis, taeniopareius, red head tapajos, to name a few. There's also some nice Satanoperca. Heros are mid to upper water, geos tend toward (not restricted to) the lower levels. There are some acara that would work in such a tank, some of them also showy. A difference between African and SA cichlids, though, is if you start with young fish, some of the SAs take longer to develop their showy colors.
Don't know how much more I can say on the subject, too many possibilities, lol. At some point you may need to just watch some videos and see what you want.
But I'd expect your list as a start would work as long as the hoplos and eel can handle water that makes the cyps comfortable.