I'd say 7 dwarf neons, 6 panda cories and 1 male with 2 female dwarf gourami (assuming you meant dwarfs?). Those should work fine together. Nice selection.
Hi,
I also think that would be okay, but I just wanted to add that in my experience, gouramis can be meeeaaaan little buggers So in a 30 gallon you may run into a few territorial problems Just a thought!!!
A trio of dwarfs shouldn't be a problem at all. Only the males are territorial and aggression isn't anything serious. Dwarfs tend to only show any aggression towards other dwarfs anyway and females aren't aggressive.