Ok.. im going to play devil's advocate here a second.
My case may be rare, but it still is a case.
I bought damsels to cycle my tank. I bought 2 of the common blue damsels, 2 yellow tails and 2 green (whatever you call em) damsels.
Since the tank cycled I added more fish, I was unable to remove the damsels due to their speed.
I have close to your set up idea. I have 2 scooters, 1 yellow wrasse and a black and white clown in there as well as a coral beauty.
My damsels never bothered any of the other fish. They did however pick on eachother at times. To this day, my damsels are doing fine as well as the other fish. I did lose a damsel, and it very well could have been due to aggression. But it was from the OTHER damsels. They fight amongst themselves sometimes, I had seen this in the beginning. But I havent even seen that in a while and all seems to be fine.
Once again, I cant say this would happen everytime, but I can say that in my tank, my damsels have only had 'issues' with eachother and not with the other fish in the tank.
As a side note, my yellow tail is the most docile of all now, he has a spot of live rock that he DEFINITELY thinks is his turf and will defend against other damsels aggressively!! But other than that he leaves everyone else alone.
Could just be my luck tho