Welcome to Tropical Fish Keeping forum.:-D
I agree that the hatchetfish and tetra definitely need more. These are shoaling fish that live in huge groups, and they have a need for a group.
Moving on to compatibility... I'm not a shrimp person, but I wold suspect that shrimp will quickly become a meal for some of those fish.
Angelfish are also shoaling fish, and in a 50g you could have a group of 4 or 5. Just be aware that this will likely result in a pair (or more) forming, and territorial issues follow. I would not keep a sole angelfish on its own, this is contrary to the fish's natural existance and thus not the best. A breeding pair (that have bonded) would be OK, again the breeding issues obviously.
Linear fish like glowlights should not be combined with angelfish, as the linear tetra are a natural food for angels. The disk-shaped tetra are better, if you go with the angels.
We have fish profiles in the Knowledge Area, so you can check out all these fish. Data on numbers, compatibility, etc is included.
Byron.