We travelled in Sicily for 6 weeks a couple of years ago, and found that Ragusa could easily fill two days, without visiting any hill towns. It's a charming little town. Make sure to visit the traditional cart maker Cinabro Carrettieri. We contact them in advance and spent a delightful few hours with one of the artists without any other tourists.
After Palermo, we made our way to our base city of Trapani. From there, we made day trips to Erice, the salt flats, Mazara del Vallo, Marsala, Segesta, Poggioreale, Cretto di Burri, Favignana, and I think Selinunte. So you might want to consider Trapani as a base for a couple of days. I would skip Scopello in favor of Trapani. The town itself is small but has a nice little historic city/town center and some nice restaurants. It was easy to become part of the neighborhood we stayed in (in an Airbnb). The people were a bit shy at first, but warmed up when we made the effort to visit with them. Sitting on the backstreet on the steps or folding chairs was a great way to get some first-hand experiences of local life.
In the Madonie, we stayed in Petralia Soprana for 3 days, which in September was quieter, and cool but nevertheless charming. Since you've got a lot less time, I'd suggest you not stay there more than a night or two. Be aware that the driving is slow going in the Madonie because the roads are narrow and twisty. You can't cover as much ground as fast as Google maps says you can. The peak season is summer when the window boxes filled with geraniums are in full bloom, but for us it was a quiet few down days. I'm sure we were the only tourists in town because we were quite the novelty. Or maybe it was because I insisted on torturing everyone with my Italian! We stayed at a wonderful Airbnb there, too. Castelbuono (full day) and the Sanctuary of Gibilmanna (2 hours) were highlights of our time in Madonie. (See visitsicily.info for more info.)