Most tetras are good tank mates because they are not aggresive and can adapt to many water conditions. All I can say about the barbs is stay away! For the most part they are pretty aggressive and bossy little suckers. They are really not suited to many community situations, except maybe a barb tank. I'd say get a good algae eater like an otto or a small pleco. there are some loaches that are good little fish to keep. The biggest stand-out in this group is the clown loach. They are shoaling fish so you will need a few of them. If you can find some, killifish are amazing fish (but they require a little mose skill to keep healthy) . Also another great group are gouramis they are very beautiful fish and are easy to please, just as long as they aren't with any of their own kind(different speices of gouramis are fine in the same tank) If you want a fairly active tank a good addition is the kribensis cichlid. They make fairly good tankmates in stark contrast to the vast majority of cichlids. There are also some shell-dwelling speices that are great in community tanks but be sure that they are fine before you buy! Most cichlids are not good in a community aquarium. There is a list of a few kinds of fish, but here are my favorites
Bleeding heart Tetra
Cardinal Tetra
neon tetra
glowlight tetra
congo tetra
fruit tetra
(painted) glass fish
harlquin rasbora
cories
flying foxes
three spot(blue) gourami (they also come in yellow strains)
Dwarf gourami
platies
angelfish
zebra/leopard danio
serpae tetra
beacon fish
hatchetfish
Kribs
pearl gourami
lyretail(killifish)
gardneri(killifish)
Panchax (any kind these are a real character fish!)
otocinclus(ottos)
clown loach
weather loach
Sorry that this list is so long, I've probably only made things worse for you. but good luck with your search. Note that eveything that I put in this list of my favorites are not nessesarily good tank mates, they are just a few standouts that I have had over the years. Godd luck, let us know what you decided on!!
I've done some research on them and I can't remember where I read it but they actually really enjoy the company of neons and other small fish. Rams use them as an alarm system. If the neons and other small fish are swimming around nicely then they have nothing to worry about. Apparently this really brings out the color in them cuz they are more comfterble.