Ok so now that you provided a screenshot I can explain you what is wrong with your economy, and why it's a lot more complex than you think it is. I don't want to be rude, we've all been there, doing these small mistakes which add up until you fall utterly behind.
Your merchant placement is wrong: the one in Persia is absolutely useless. Persia only flows in Aleppo, so the money there is either collected in Persia or steered to Aleppo. You hold every province in Persia, so noone can collect. So by default all the money will be steered towards Aleppo and your merchant literally does nothing. Collect in Constantinople for +10% income.
What I called strategic conquest is conquering areas that will bring you something, either in term of expansion opportunities, AE management, income or blocking of someone else (and culture and religion to avoid revolts, especially at the beginning). Once you're at your state limit, development or trade goods only marginally matter. That's why India is SO important to conquer early on, it gives you the best unstated income of the world thanks to TC. I understand Malwa may be too big atm. But taking Hobyo and Kilwa seems relatively easy, they are probably behind in institutions so they should not be ahead of you in miltech. That gives you a TC, and a merchant, which you can use to transfer in Alexandria and get another 15 ducats from trade, and that opens a new front, Africa, in which you probably have 0 AE atm. Kilwa also usually has several thousands of gold to steal.
Your gold income is 0,5. This means Kosovo is probably not stated and not developped. This could very well have been 5 ducats since 150 years, that only seems like a small loss but that's almost 7500 in total! Think of all the manufactories you get from just thinking about this.
That brings me to my main point, economy is ALL about the snowball. Small gain allows to build one more building, which means more small gains until you drown in ducats. You say your economy is good because you make 50 ducats in peacetime. Sure, that's OK, that means a manufcatory every year, considering you also spend money on other things. But that should be so much more, which would mean even more, and more, and more, and that's quite easy to fix.
You have 13,66 state maintenance. That seems a lot to me, but maybe you don't have edicts at all. Check it, still.
You have 19 freakin fort maintenance. In peace time. As the Ottomans, you will probably literally never have to defend. Tear down every fort on day 1, and don't build any. Destroy every fort you conquer. Sure, that means some unit might sneak and start carpetsieging you ocasionnally, but that's so small compared with what you lose. 200 years of game, 10 ducats per month on average, literally almost 25000 ducats! Think of all the buildings that fuels, or the mercs that buys to save manpower and conquer faster, which allows to reach India earlier, before it's united, and then to have trade companies there earlier, and more merchants, and more income, and more mercs, and more conquest, and so on and so on. And that's why a ridiculously small mistake costs you so much in the end.
Army maintenance and fleet maintenance are maxed out in peacetime, with no revolts over 80%. Waste of money again.
You take attrition in peace time with no incoming revolt. Waste of manpower and of money. And so on and so on.
As for tech, I legit do NOT understand what happened with tech. But going coptic and losing the best government form of the game might explain it a bit. Some people will tell you coptic is better and that's probably true... but a lot harder. Play it safe! Sunni means Dhimmi in every heathen province so another 25000 ducats since you started or something like that. It means good rulers all the time, so a lot more monarch points.
With the pace of your expansion, you don't need Deus Vult, you need stability to focus on the basic economy and save up manpower, so why turn all your land into wrong religion because some redditer who onetags in 1700 told you that was better, that's not the same game you two are playing. Use dead tags (Syria, Iraq, Armenia, Transylvania, Persia if possible, ...) That saves AE on top of costing 0 dip to reconquer. Admin is a must have first, then Influence, and this synergizes perfectly with vassals. That gives you "unjustified demands", a godlike modifier that allows you to conquer more land for less dip even with conquest CB. Now that Deus Vult is last in Religious you can't have it before 1530. Absolutism unlocks in 1610, I'd make sure I have Humanist instead of Religious anyday. That's trading dip points (almost useless resource, as only dip 17 is a meaningful dip tech if you don't colonize) for manpower (you don't have it so that's good) and absolutism in the long term (godlike resource).
Another explanation might be institutions, but even by totally messing up I don't understand. When I start a game as the Ottomans I can have positive income even when I build mercs up to force limit with level 2 advisors, and this insane 6/6/5 ruler (but that's because I micro estates to squeeze every ducat). That brings you all the techs you could ever need, especially as you'll have over 50 PP once you annex Byzantium. You'll drown in MP by the time you can forcespawn Renaissance (with proper estate management once again to reduce dev cost).
All of the things I point are things that are not required for a WC, just required for a successful campaign, even if there is no shame in not knowing them. That's why I asked you if you were sure you wanted to do a WC in the first place.
Because on top of that, WC requires a lot more agressivity in the pace of your expansion, which requires yet other skills and complete understanding of coalitions, overextension and absolutism.
Maybe try to play a tall game to understand some mechanics, around Italy or Germany for instance. With 4-5 provinces it's a lot easier to see that it isn't "just putting merchants in trade nodes, where you have provinces, giving estates provinces if they have less than the required provinces and taking monarch points from estates every 20 years and building manufacturing/taxation buildings everywhere?"
And once again I do not say it to be rude even if that may be hard to have so many flaws pointed. And feel free to PM me for any detail or any generic question.
