Just got back yesterday from both Croatia, Slovenia, Montenegro and Albania.
Slovenia: all the north west side running down from the Dolomites South tirol, italy. Triglav Nationalpark and Bled.
Sidetrack: Montenegro is amazing, especially the mountainous east, green... riders dream. Recommended and not far from the Dubrovnik (HR) cheap, just take the green insurance card.
Albania is my favorite country from the lot, road conditions are pretty rough but worth it if you like adventure and a bit of gravel.Lovely people and not so many tourists. Blue line ferrys from italy, cheap and good. (sorry for the sidetrack)