x4 silver dollars (try finding fasciatus or maculatus those are super cool but hard to find)
x5 clown loaches
a pair of senegals or a pair of delhezi bichirs or maybe one of each
BGKF Black Ghost Knife Fish are really cool
Silver dats are nice and stay max out at a good size for your tank
Maybe a group of Leopard Ctenopoma?
A group of Geophagus species are super cool. Satanoperca Jurupari are nice.
A group of Pink Tailed Chalceus? There is the yellow fin and pink fin, your choice.
And don't overlook plecos. Some are really worth keeping. Maybe try a phantom or a snowball pleco? Not too bad on price, active, get a good size, and super nice.
What about a lot of rocks or driftwood for a fire eel or tire track eel? Super nice fish if active.
If you're looking for non-cichlids, the ones listed have got me lovestoned.
They all should be compatible so maybe choose a maximum of 4 species depending on grouping or singles.
I'm just thinking if I had your tank right now haha.
I hope my suggestions interest you! Good luck!