Yes I have kept Randals, Sunburst and Dispar anthias. They are all peaceful, so I don't think you will end up having an issue. I would get say one male Randal, one female Randal, one female dispar and 1 or 2 sunsets. I think you will be ok there. The problem I have ran into with anthias is that if you have a semi aggressive anthias say like Barletts. They beat up there females allot. If you would get a male Bartlett and one of other species and they should turn to male. The Bartlett would try to kill any other male in the aquarium and try to take all the female anthius regardless of species. Just FYI.
Now going to the orchid dottyback. I have never had a orchid dottyback, but I have had a splendid dottyback and he was really mean. I wouldn't get that fish unless it was your last one. It may put all your anthias in the floor.