Granted
the King of France please!
Granted
Parliamentary England please.
Granted
...you got me; Montrose please!!!
Granted
I would like to have the kingdom of Sweden please.
Granted
Can I take King Phillip IV of Spain and Portugal?
Granted
At this rate, I may need to open up more characters.
I reckon both 'main' British factions could contain more or less infinite subdivisions if necessary (indeed in your position I would possibly have limited the game to the British Isles, but that's your choice and I'm sure it will add an exciting European dimension!)
But it would def be fun to play as, say, Waller or Lambert on the Parliamentary side, or Sir Edward Hyde or Rupert on the Royalist
Also wonder if Ireland should be divided like Scotland? At this point the Confederates were pretty totally active rebels against Charles's forces under Ormonde and Antrim...
Ignore all this if too annoying / no more players needed of course
(and forgive my ramblings, this period is presently the closest thing I have to a day job!!!)
EDIT: other thoughts if nec: Netherlands? Denmark? Protestant German princes?