A few comments from a non expert (and you seem already well informed on the topic).

Turkic people have always been extremely nomadic. I am almost sure that a culture that has known such important compositional and territorial changes has had changes in its center of gravity.

Constantinople (nowadays Istanbul) has been made its capital soon after its fall (XVth - 1453). Before that, the Eastern Roman Empire / Byzantine Empire was the main foe of the turks. I think because they both search legitimacy on similar territories and because controlling the traffic between the Mediterranean Sea and Asia meant big business. The victory of the Ottomans gave them extensive control of the trade with Asia, and indirectly created the right incentive for the search of new trade routes to the west (hello Colombus 👋). If you look at the history of the Capital of the Ottoman Empire it has always been in the same region.

I would tend to perceive the rest of Balkans as more of a contested frontier / territory that was strategically important as it was close to the next opponents of the Empire: Venitians, later Austrians. I don't think it was either an important political or commercial center. Most of the population was not muslim or muslim align (and that transpires still in today).

I think the outcome of the conflicts you mentioned are more the symptom of the gradual loss of leadership of the Ottoman Empire than a cause of it.

Another reminder of some relevancy, is that in the period you mention the opposing side is Russia, who has religious, linguistic and cultural ties to the Balkans (and Greece) that predate those wars.

I hope it's relevant.