Yet another dlc that does not add anything (nothing good at least)
Conclave is proof that Paradox has to stop releasing more dlc for CKII: anything they add at this point is either trivial or actually detracts from the fun. Conclave's main concept is a council that interferes with the ruling king or emperor's decisions. It is somewhat enjoyable when you are a nobleman who can use his council seat to indirectly change this in the kingdom to your advantage but that's where the fun ends.
Even if you start out as a vassal your ambition should always be to become an independent ruler yourself. And once that happens the council is just plain annoying. The ai just randomly changes policies and opposes actions for no good reason (they actually consider it tyrannical if I order the arrest of someone who was plotting to kill my heir). I actually found it quite easy to bring the council to heel, but even doing that isn't enjoyable.