Definately not expert but used to keep FOWLR tank thus i can help you in some angel's infor.......
1)Emperor angel- adult emperor can be rather territorial and no two adult angel should be kept together unless you want death. Need a big tank with lots of rocks for hiding, shy fish at first but once it is acclimitize, it will start eating greedily. Moderately dfifficult top keep as its skin is prone to infection and also commonly attack by ich.
2)Majestic angel-similar to emperor, majestic can be rather territorial. This angel will go into hiding for few days when added to the tank but once it come out to feed, it will be like a pig.
3)Blue faced angel- more delicate compare to emperor or even majestic but do better when small. Nice fish with fierce attitude, mine used to attack my damsel. When added to tank, this fish sometime may go in the state or shock darting ard crazly. Once again big tank is needed.
4)Passer angel- rather hardy for angels and easy to get them to feed. Mine uncle's passer has been in his tank for already 9 months and btw they need big tank because they grow to a large size.They are aggressive and territorial and not really safe with brains.
5)Rock beauty angel- this fish is very delicate and hard to keep. Should be left to the more experience. They need very aerated water and keep water condition good.
6)maculosus angel-very hardy but they are rather shy. When added to tank, it may hide for few days then come out to eat. This angel are big when adult and i mean big thus a tank of at least 5feet is needed.
7)asfur angel- requirement same with maculosus but they are not that hardy compared to maculosus angel.
8)flame angel- hardy and getting them to feed it rather easy. They may nip brain or even clam mantle so care must be taken.
9)regal angel- very hard to keep and difficult to get them to eat. Water condition must definatley be good. And red sea specimen are much nicer compare to those indo pacific ones.(x-japan kept one for very long time, maybe you might want to ask him for those who wish to own this beautiful angel)
10)coral beauty- hardy but need to have good water condition. They may however nip at clam mantle or brain coral.
11)bi- color angel-delicate fish and hard to get them to eat. Water condition must be good and they might nip clam mantle or even brain coral.
Once again most of this info are from net and some are from my experience. Different people may experience different kind of characteristic even though they maybe the same species. IMO if you want to keep coral, try not to have angel even though some ppl say that their angel have success with corals.