For your stocking, I would up your schools. You have space, you can certainly get more than 4 in a school. They tend to school better with more fish anyways IME, and the angels will likely inspire them to school up. Yes, angels can eat neons. Sometimes they do, sometimes they don't. Hard to say. As has been said, you have a better chance of it working with bigger neons and smaller angels to start with.
In addition, you can look into more platies and mollies. Those are both great fish that come in tons of colors and you can easily get a big variety.
A couple dwarf gourami should be fine. They can be territorial, but that is a fair amount of space for that size fish. You could instead do a single opaline gourami or somehting similar. I don't suggest a gourami trio, because you don't want too many potentially aggressive fish breeding in the tank. With 4 angels, it is likely you will get at least 1 pair and you will have to keep stock that is compatible with them.
I agree, no parrot fish.
Some other options, a school of cories or small loaches like the yo-yo or zebra. A dwarf cichlid like an apisto or ram. There are also bristle nose plecos or farlowella that are fun to keep.