The angels and clowns sound fine but keep in mind that the loaches will eventualy need to be moved to a 90 gallon (will take a long time for them to reach a good size though so not a problem at the moment with a relatively big tank like you have).
Also, I personaly would say that mollies would be fine. Only the real wild-type species of molly realy need brackish conditions. Those you see in your LFS have been bred generation after generation in all sorts of water conditions and should be fine. Keep in mind they get to 4" though. Many people under-estimate their potential size. Males are smaller than females.
Puffers are a definite no.
By leopard fish, do you mean the ctenopoma/bushfish? If so, I personaly wouldn't keep them with angels. It may very well be possible to do. The leopards don't get that big (around 6") and aren't realy that aggressive (except territoriality towards each other and the chance of them eating smaller fish) but having 3 pairs of potentialy aggressive (when breeding and paired up) cichlids (the angels) with some of these ctenopomas which would also be aggressive when breeding is probably not a wise thing to try in a 60 gallon. Though, if the tank is densely planted, it may be possible provided you match the ctenopomas' requirements and maybe reduce the number of angels to 4 and stick to a single pair of the leopards.
BTW, you don't realy need to worry about the parameters (I mean pH/hardness) for angels. They have been bred for so long in so many conditions that they are now hardy fish and can be kept in pretty much any pH/hardness and environment provided the water quality is good.
I'm not sure about the ropefish but you'll probably want to ask in the oddballs section if you are still considering them.
