fish-aholic
Fish Crazy
Would say three pygmy cories be ok with three ghost shrimps and 4 zebra danios.
I would consider carefully before putting the pygmies in with any other fish that could get it in its mouth or is a serious nipper. You may find the numbers slowly dwindling over time. There is an old fishy addage regarding fish small enough to fit in another fish's mouth.
Really, many fish will eat their own fry.