as you probably know SOME plugins travel without any problems,
others dont.
After Effects type plugins probably are the ones that dont travel,
or plugins that require more complex licensing
& there's probably legal issues involved (the other system hasn't shelled out the $$$ for those plugins)
but yeah, what you say makes sense.
FCP should give you a bit of a helping hand to let you know what plugins you'll need,
and also as you say, maybe help you gather them.
SAME GOES FOR FONTS
nick