Specializing Client States with extra tier of Treaties

I think Independent People can be made more worth keeping by giving them more customization. I propose the following Treaties to be given to Client States to specialize them further:

• Tributary

Prerequisite: none

More Money income

Can not recruit Mercenaries, and maybe disband their defensive armies

• Mercenary State

Prerequisite: Standing Army or Organized Warfare, Mercenary Armies Civic, Violent Independent People

More Mercenaries, stronger Mercenaries, upgrades armies automatically following Overlord technology progress

No Money Income and no Science Income

• Buffer State

Prerequisite: Siege Tactics and/or Imperial Power

Bonus Combat Strength for Independent People and Overlord when fighting in this IP's territory, mercenaries and armies upgrades automatically following Overlord technology progress

No Money income

Independent People prevents Sphere of Influence spread beyond their Territory (both ways, goal is to prevent Grievances from Overlord and Empires bordering the IP)

• Religious Haven/Refuge or Ghetto

Prerequisite: Taxed Minorities Civic or Banish Unbelievers Civic, at least 2 Religion present on Empire AND [ 2 Religions on IP or Overlord's State Religion absent on IP ]

More Money income (only for Taxed Minorities Civic)

Increased faith share and pressure for state religion in cities of Overlord (only for Banish Unbelievers Civic)

Independent People Territory becomes immune from religious spread from Overlord's State Religion (and by extension, no religious patronage for Overlord) (for both Civics)

• Colony

Prerequisite: Supply Lines, Vassal Colonies Civic and at least 1 Resource on IP

Provides Resources for free for Overlord (no license, no maintenance), and maybe more Money income (and maybe more Resources ?)

No Science Income and no Mercenaries, as they are dedicated to resource extraction.

• Penal Colony (additional option following Mark1812's reply)

Prerequisite: Supply Lines, Vassal Colonies Civic (not so sure about that), IP is located on a different continent than the Empire's Capital

Increased Stability on Cities located on a different continent than the IP

Increased faith share and pressure for state religion in cities of Overlord (only for Banish Unbelievers Civic)

Independent People Territory becomes immune from religious spread from Overlord's State Religion (and by extension, no religious patronage for Overlord) (only for Banish Unbelievers Civic)

Reduced influence of Sphere of Influence of other Empires on Empire cities (maybe not up to Territories too) (only for Monoculturalism Civic)

Independent People Territory becomes immune from Overlord's Sphere of influence (and by extension, no Sphere of Influence patronage for Overlord) (only for Monoculturalism Civic)

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