I would only prophylactically treat with Prazipro (for flukes) and only after copper is complete. All other diseases which require different medications show obvious physical symptoms. Ich, flukes and sometimes velvet are the "hidden diseases" I treat for without waiting for obvious signs to show up. Remember, all medications are essentially bad for fish and you have to weigh the risk/reward of preemptive treatment. By adding a PBT into the mix right now, you may be forced to expose all of your fish to antibiotics or some other medication they don't currently need.
If you add a decent sized PBT down the road, you won't have to worry about it being bullied. More likely the other way around.
I see, last time I did QT a few years ago on many of these fish I still have in fact, I did Copper and Prazi treatments (not at the same time of course), which seemed to work well so I'll probably do that again here. Maybe this is an excuse to put my 29G QT in the office back into production so I could QT at the same time but keep them separate. Decisions, decisions ;Smuggrin