I've really enjoyed following this timeline over the last couple of years, but I don't believe I've ever commented here before, and since I had a few idle thoughts and questions regarding the Balkans ITTL I figured it was high time to rectify that.
Firstly with the Danubian principalities being freed from the Ottomans, it seems likely that they will be unified fairly soon (if they haven't already). Since Russia will have a great deal more influence over this process ITTL, is their any chance that the Wallachians and Moldavians will settle on a different name for their new kingdom than Romania? IIRC the Greek Plan of the 1780's had planned on uniting the principalities in the Kingdom of Dacia, and since the Russians liked to portray themselves as the third Rome, would they be cool with their vassal kingdom proclaiming itself as Romania? I don't know how much the Romanians themselves would care about the name for their new kingdom, but if the Russians end up forcing them to pick and exonym, maybe it could make them a bit more apprehensive about their new patrons?
Another thought I had is about Bosnia ITTL and whether or not it could potentially be feasible for an independent (even if only nominally) Muslim kingdom to exist in the region. The Ottomans will almost certainly end up loosing their grip on the region, but unlike OTL the Habsburgs might not be in a position to grab all of it for themselves. Similarly they presumably wouldn't want Serbia to have it either, as that would threaten their hold on Croatia. Is there any chance then, in the interest of regional stability that the Austrians might support an independent Muslim buffer state in the region? I don't know how the great powers would react to this, but with the British and French having couped the pro-Russian Serbian government, maybe Russia could either support the Austrians against the Serbs in this matter or just not oppose them? If the Hungarians have plans of reclaiming Croatia, they might potentially also support this as a smaller Croatia would be easier to integrate, and similarly they also wouldn't want the Serbs to have it. Alternatively Serbia and Austria might also just end up carving up the whole area in a way that satisfies both parties, but I think the idea of an independent Muslim Bosnia existing in the Balkans in this era would be fascinating - even if it probably is very unlikely.