As far as I know, Tetras aren't generally fin-nippers, but I've never had skirted Tetras and maybe they're different from Neons, Glo-Lites, and the like. Tiger Barbs and Danios tend to be a bit nippier.
Neons are Angel food in the wild. I would assume that Angels don't see much, if any, difference between Neons and Cardinals, but I don't know that for certain. Some Angels will leave Neons alone, though. I guess it's just a trial-and-error type thing.
Don't know much about Silver Sharks...
I'd be cautious about putting a Betta in with an Angel.
Sorry, bugsy, I'm not trying to shoot down everything you say
Just giving my opinions....
Depending upon what kind of Pleco you have, he may get too big for your tank. Common Plecos (and many other Plecos) can grow to be well over a foot long!
Corys and Rams are both great little fish, as are Loaches. Kuhli and YoYo Loaches are both okay for a 30 gallon. There are probably other loaches that are, as well, but I'm not sure which ones.
Guppies, Platys, and Swordtails should all do okay with Angels, as should Rasboras.
The possibilities are nearly endless!
Pamela
aka Married Lizard