I use master sync on most of the time. It's very useful for setting up dependencies that are masters driving sub masters. At the return to 0 the subs automatically back out.

There's no issues with Antonia and master sync(h), I use it on with her hundreds of times. 

Hiding dials is kind of pointless now that Poser has a show hidden parms checkbox. But if you want a bunch of extra clicks for some reason set the parms as hidden in dial settings or by hacking the cr2. Probably doing it in a text editor is quicker I guess. I just do it as I go along in settings as necessary.

For parm groups; I create a parm group in every actor that might contain a FBM component. It helps keep things neat if you are creating and sharing a bunch of morphs.

For JCMs I create a JCMs parm group in all involved actors, so too with FBM. Though every JCM I create is in a sense a FBM as I use an empty FBM dial as a master for all controllers and JCMs. That is if the target is pmd. For cr2 embedding create new master valueParm is fine.

Save yourself the headache and create parm groups preemptively and descriptively named for destined actor specific morphs, if that makes sense. I have mine transparent to the user but collapsed initial.