In the long run it's best to keep Angels either in established pairs or in larger groups of at least six fish. In a trio, 2 might pair off and then shun/bully the gooseberry. Nice Angelfish article here:
http/www.thinkfish.co.uk/article/Angelfish.html/
If I were you I'd forget about the redtail shark in a community tank. They are ok as juveniles then tend to become more and more belligerent with other fish as they mature.
Edit: Angels grow large enough to eat Neons! Gulp!!