The world is your oyster as far as cardinal tank mates go, pritty much any other tetra, cories, barbs, guppies, mollies, platy's. The list goes on Just research fish that'll fit in your tank and chances are they'll get along fine
Cherry shrimp are relatively small but the fish species you will be buying will not be big enough to really consider them a snack. In a tank of your size I would try to avoid live bearers as you will inevitably end up with loads of fry which won't all get eaten and your tank can quickly become over run. This rules out guppies, platies and mollies. Mollies also do better in slightly salty water so I wouldn't reommend them for a new freshwater tropical set up anyway. I would say go for 6 cardinals, 5 of another small non live bearing species, 5 pygmy cories maybe some honey or sparkling gourami as a centre piece.