Will you fix the Subjugation CB? Sometimes subjugation of country demands over 100% warscore. Also, subjugation generate a lot of AE. Looks like It just needs fixed warscore and AE and then these missions will look great.
UPD: You granted special 1st tier reform for Ayutthaya, but Mandate of Heaven is also special 1st tier reform. Does this not contradict each other?
Subjugation already gives you 50% WS cost, so you can vassalize something twice as large you normally could. I don't think it should work as PU CBs do, being able to vassalize some 1000-dev behemoth makes little sense. (Just like it makes little sense for the PU CB to work the way it does.)