The Thirty Years War [Concluded]

[Ibn-Khaldun]

Basically, yes.
Though, you can have as many Militia and Mercenary armies you want since they don't need generals to lead them.
Also, if you want several fleets(with warships) you need to expand your RC since Admiral recruitment works just like General recruitment.

split is correct. If Royal Court becomes too huge PO will decline plus couple of other things might happen(no, I am not going to tell you what).