If you have a sorority in a 10 gal, which I'm assuming you've got about 5-7 females in there then you really can't keep any other big showy fish like the ones you mentioned. The bio-load would not be able to handle anything more unfortunately.
Generally though, gouramis and betta's are pretty much a no-can-do because they are both cousins, they both have the labyrinth gill making them both mid-top level swimmers and are territorial.
Cichlids are usually just too aggressive or have different requirements then your girls. Ram's are generally a nicer cichlid, aren't as territorial unless they're breeding. But they require an extremely stable aquarium to thrive.
Leopards: 1:4 Hawkeye, Luna, Astrael, Dorian, Cullen