I can be healthy and alive in a coat closet with another person, a very clean coat closet, but I still wouldn't be happy, and I might very well start elbowing the other person out of the way so that I can have a little more space. Now if I had a razor sharp scalpel on my elbow, and was generally not too friendly to similar humans, it could get rather ugly over time. If I was in the coat closet with a dog, it might not be as bad, as quickly. In short, I think some of the tangs in that tank should go.
The fact is those fish will not all last in that tank, I think we can agree on that. I think we should strive to keep the number of fish in a tank that will fit there as adults. Not trade them out or replace them like commodities. I have no problems with fish only tanks at all, but just because it is fish only, doesn't mean you can cram it full of fish, even if you have the filter to handle the waste and someone to clean the algae. From the picture, there are very few places to hide, and this I do have a problem with, fish only or not.
That is a tank designed to make people ohhh and ahhhh, as are the tanks at lovely places like the Rainforest Cafe. It is clearly well taken care of, but the fish are still there for human interest and not so much concern is given to the actual fish. We should strive to do both, to some extent, and I think many people would agree with that.
There wouldn't be harm in taking a few of the tangs out, and adding a bit more decor for hiding. How old is that tank, BTW?
Anyway, that is my philosophy. However, I am well aware that it is not widely accepted.
You can't go wrong with a foxface, IMO. Great tough fish. Just remember that the dorsal spines are venemous, like a lionfish. You must know where that fish is at all times, and do not startle it. Sometimes they can get a bit skitish.