Consiglio Bikepacking

Hello everyone, bikepacking enthusiasts and non-enthusiasts 🙂
I've been cycling for a few years now. I recently turned 30, and I wanted to raise the bar on my travels. I usually travel alone, gravel-riding, mostly on dirt roads. Last year, through social media, I met a guy who was as passionate about cycling and travel as I am, and we took a short 5.5-day trip through five European capitals (Ljubljana, Zagreb, Lake Balaton, Budapest, Bratislava, Vienna).
This year, we've both raised the bar. We have 14 days of cycling ahead of us, in the former Yugoslavia, covering about 2,500 km with 25,000 meters of elevation gain and more. I wanted to ask for advice from anyone who has already traveled through these countries.
We'll pass through Croatia, Bosnia, Serbia, Montenegro, Kosovo, and Albania, before returning to Bari by ferry, then continuing towards Naples, taking the coastal road (Salerno/Naples).
I wanted to ask for advice on if, how, or what we should be careful about. These are new countries for both of us, except for Croatia. Now, parochialism and prejudice are useless. We had a truly wonderful time in Hungary and Slovakia, wonderful people! We just wanted some opinions, from those who have already cycled through the Balkans!
I forgot, everything will be on secondary roads, but on asphalt!
Thanks for your time!!
Have a good trip everyone!