There's about a 50/50 chance (estimating) that if you get dime-size angels the same time you get guppies (guppies are in/go in before angels) they would live peacefully. I'd say that angels can't live in a 30g. Although I don't really like guppies (all livebearers (besides some swords and mollies), they're just soooo common and plentiful), here's a stock list:
6 guppies (2 male guppies, 4 females)
6 cories
6 rasboras
6 tetras (not neons or cardinals, lemons, glowlights, serpaes, etc.)
This would be a schooling tanks, from rough-schoolers (guppies, somewhat cories) to complete schoolers (tetras, rasboras (?))