Your proposed stock is already really heavy. Clown loaches eventually grow to massive sizes, as do some species of silver dollars. The Heros themselves are no slouches -- I kept eight large Heros in my 6' 210g and that was still tight quarters when the spawning started and the pair shoved the other 6 fish into the far right corner of the tank.
If you want other cichlids, I'd suggest considering pruning down the numbers of loaches and silver dollars you plan to have, or maybe consider substituting them for smaller species.
As far as cichlids go, Heros are very versatile fish. I have kept them in 150 - 210g tanks with nearly everything -- Hoplarchus, Crenicichla, Geophagus, Andinoacara, Aequidens, Acaronia, Hoplarchus, Hypselecara, Symphysodon, Pterophyllum, Bujurquina, Acarichthys, Herotilapia, Crenicara, Heroina, Krobia, Mesonauta, Laetacara, Uaru, Retroculus, and even Pelmatochromis. There is a reason Heros is my favorite genus. They're compatible with nearly every cichlid I've ever kept, as long as the fish aren't too small or too aggressive, and the tank size is adequate.
I think six Heros, a centerpiece fish like a pike or Hoplarchus psittacus, and some smaller dithers would make for a nice setup.
