Keep in mind that with most of the larger Angels (10-14 inches) require about 125-250 gallons bare minimum. So, with a 400–450-gallon tank you could likely keep only 2-3(at most) in that tank. Dwarf Angels it would be possible to keep more - may be 4-6 of those.
So, what at about a nice FOWLR set up? Pick your favorite large Angel, Add a Trigger, a puffer, an Eel or two, and a few smaller fishes, like Damsels, chromis, tangs, with maybe a dwarf Angel, & a wrasse or two.
Or Maybe a Nice predator tank? A Coral Catshark (or 2), A yellow or cortez stingray, An Eel (or 2), and maybe a small grouper.