The complete removal of Divided Patronage is no longer a thing from the vanilla Civic and AP. They are now +1 each.

Out of all my mods I thought this one would be the best one to address giving this change a vanilla+ makeover.

Ideas:
Prestige Ruler Trait Option: +1 against DP (No guarantee to get, some rulers just handle vassals better)
Traditions: Modify Domination and/or another one to give -25% effect against DP. (More help for lots of vassals less help for few, triggers after the flat reductions)
Late Game Tech: +1

So by late game, and if your lucky with your ruler you can have a total of (DP -4) * 0.75 (min 0).

If you still plan to vassal spam with say 10 vassals, you still have a DP of -4.5 which seems reasonable for late game, as opposed to -8