An idea: Spanish and Portuguese Colonial Nations should get Peninsulares, Creolles, Clergy, and Landowners.
Peninsulares are those of European families born in Europe and moved to the colonies. They were mostly the administrators until later on when the independence movements started brewing. They should give administrative bonuses. Cheaper cavalry too for gameplay sake.
Creolles are those of European descent who later became a big percentage of the middle class and thus should be the ones that give more income tax and cheaper infantry.
Clergy is clergy, mostly Catholics.
Landowners are plantation owners who should give production tax.
Peninsulares with too much power would make the Creolles and Landowners unhappy. Likewise with Creolles having too much power will make the others upset. Landowners with too much power may trigger slave revolts. Clergy with too much power will slow down your technology.
Haiti could get special flavor, Saint-Domingue (original name of Haiti) colony could get Grand Blancs, Petit Blancs, Clergy, and Mulattos. Maybe assign this to all French colonies not just Saint-Domingue.
Estates has a lot of potential for different countries.