Hey Mike! If I could throw my 1 penny in... Well, now I guess it's 3 pennies... Inflation and all...
My 55 Community, when I picked it up was already home to a very large Angel, 2 Hatchets, 2 headlight/taillight tetra's, 1 neon, 1 black molly, 1 von rio tetra, 1 cory, and at the time, 2 very large pleco's. The tank was horrendous when I got it. It hadn't been cleaned in about 2 months or longer.
Not trying to tip the balance too much I re-homed the large pleco's, and opted for an albino bristlenose pleco, and added 2 platies, 3 glo fish, 2 clown loaches, 1 killie, 2 more glo fish, a red finned tetra, and an SAE... Authentic no kiddin SAE.
I have a bunch of live plants, don't use CO2, upgraded the lighting, and i'll tell you that Angel, is the Matriarch of the tank. She only gets mad when the glo fish bump into her when they are doing their Danio thing... You know, running amok... *LOL* I know that there are several fish that are supposed to be schoolers, but i'm assuming that these kids were all brought up in the tank together at it's inception about 4 years ago. Somehow it's working. All fishy kids are flashy and healthy, no in-fighting, other than when the molly gets stupid with the hatchets... Maybe not the best setup in the world, but they only mess with the plants when the bearded algae makes it's appearance.
I wanted to add more SA fish to it, so I tempted the fates with 3 GBR's. It's still working. No issues. Am I tempting the fates? Yeah, probably...
Ok so that's my 3 cents worth. For what it's worth....
Thanks Mike