does displacing the ottomans still give you similar military potential (in forcelimits, income, and manpower?) I know you won't have ghazi but that is just for manpower regen.
As far as I know you cant tag switch from Ottos to byz anymore.
Also yes by removing the Ottos from Anatolia you get an event that increases manpower and you get some base tax in the capital.
Also the triumphs give some hefty bonuses, don't know if it comes to the same standards as the Ottos, but when I take over Anatolia, I never seem to run out of manpower again. Province stats don't change by province owner, but you get the "Restore the Theme system" decision that gives you a 20ish% boost in manpower if I remember correctly.
Question: Is it better to stick to Orthodox or switch to Catholic? If Catholic is better what's the best way to switch?
Never Switched, you need the Orthodox patriarch authority IMHO, in order to help convert all that Muslims and keep revolts down. Especially if you plan to push through the middle east (which you should regardless of your other plans). You counterbalance the tax drain by passing the ''Church taxes'' NI.
Religious Ideas, 100% Patriarch Authority and Byz Ideas should be enough to convert Mecca and Rome.
If it isnt you can pass a couple Missionary NI. But its not necessary, divine Supremacy event will hit often.
The only benefit I can see to switch to Catholic is for joining the HRE early on and boosting relations, but it is a big gamble and I think unnecessary. You need to take a latin OPM in Italy and move the capital there to do that. Or one of the Balkan catholic provinces.
The only bonus I can think of is the curia, but I doubt you will be able to control it.
Albania is now a vassal. Would it still work if I annex them and then send in the missionary? Also I suppose I should get my orthodox rating as low as possible, right?
Doesn't Albania start Orthodox?
Patriarch authority doesn't count when religion switching as far as I know.