Well my dad has had at least a 75 gallon tank since his second year of college, so he has quite a lot of experience, I think the angel had an issue when he got it, it looked good in the display tank but since we got it home it had strange swimming patterns, even for an angel, and it didn't eat very much. As for the mandarin, I haven't read anything about them being extremely difficult eaters, but that's the fish that I've read least about on this list. I have no problem buying specific foods, and tong feeding if necessary, as a matter of fact, I have been buying Hikari anglefish food and feeding the rock beauty with tongs, as that seemed to be the only way to get it to eat. As for the wrasse, I've read they may become aggressive if introduced to another male, but in general conditions they are rather passive, and don't harm anything except crustaceans they can eat. I haven't seen a tuskfish at my local LFS, are they fairly uncommon? I like their colors quite a lot, but I really loved the personality of my old wrasse. This tank btw is very well aged, we've had it set up since I can remember, and I'm 19 now. I will be siphoning about 70% of the water into 55gal containers when I move it, then putting the water back in. i will also be keeping the dead coral structures he has, and adding live rock, so it should be very stable.
Ken