Just my two cents, this is kind of a strange stocking list.... You have several species of schooling/shoaling fish, but not in sufficient numbers to see the behaviors that make these fish interesting or to keep those fish comfortable. I get that you want larger fish, but it's hard to have a lot of larger fish in a tank that size. If it were me, I would pick your centerpiece (usually larger) species first, and then work around it for the other fish. A few ideas:
(1) If you really want those particular rainbowfish, make them your centerpiece and get enough to make them comfortable (from seriouslyfish.com: "Like many other rainbowfish it can be quite skittish and does far better when kept in a shoal of at least 6-8, preferably more. The males will also be encouraged to display their best colours in the company of conspecifics. Obviously a suitably-sized aquarium would be required for a very large group.") Get 10-12, and then fill in with a dwarf gourami (if compatible), and perhaps a small school of a dwarf catfish species (Hyalobagrus flavus or Hara jerdoni if you want to stick with Asian species, or a few cories if you don't mind mixing continents).
(2) If you want cichlids as a centerpiece, this is a suitable footprint for a group of 6 Bolivian rams, (seriouslyfish.com: "M. altispinosus is a relatively gregarious cichlid and should ideally be maintained in a mixed-sex group of 6-8 or more."), a pair of German blue rams, or a group of Apistogrammas (1M/several F). Then you can add a nice school of small tetras (even up to 20+ if you pick a small species), and a school of Corydoras if you want (though the rams will inhabit the lower part of the tank, so Corydoras are necessary aesthetically).
(3) If you want gouramis as a centerpiece, try a group of honey gouramis and fill in with a nice-sized school of small rainbowfish or rasboras, and again, a school of catfish or corydoras for the lower areas.
(4) If you want the biggest centerpiece fish possible, you could also do a pair of firemouth cichlids in that tank -- males get up to 5"-6" long. These are beautiful fish with great personalities. But I don't think you can keep smaller fish with them, so not so great for a community tank of this size.
Caution: Check with aqadvisor for whatever stocking you do. It's okay to overstock somewhat as long as you're good with water changes.