I'm trying to form a logical itinerary for September 2019. I'm thinking September because I'd like to miss the heavy crowds but still have nice weather and services. I typically rent a car but only when other forms of transportation won't serve my needs. I'll likely have 20-21 days, ideally no more than two lost to travel to and from the US. I don't like backtracking when I can avoid it. This rough outline has too many stops so I welcome suggestions both how to get places and what should/should not make the final cut as I pare back.
In the south, I'd like to see Kotor and Dubrovnik before working back toward the north. I don't see renting a car at this point. What are good options/routes for getting there without losing too much time? Flight? From where? Would you go to Dubrovnik then bus to Kotor and back or go straight to Kotor and bus to Dubrovnik?
From Dubrovnik, I envision ferries to head north along the line of Korcula, Hvar, Split/Torgir. I like biking so would be perfectly happy renting a bike to get around on an island up to about 50 km a day, not too much more than that. I'd also like to visit Zadar. From there I would like to continue going north, by ferry if possible, to see more islands, Kornati, Losinj, Cres, Krk.
Some of the questions are if ferries are readily available to cover the itinerary and whether walking on is the best way to use them? Is there a good site for ferry routes and schedules?
After I've exhausted using ferries for islands, I'd pick up a rental. I'd like to get to Plitvice but this may be too much out of the way? I'm also interested in adding Llubljana and Bled in Slovenia, perhaps then coming back through Istria, returning the car in Rovinj, then ferry to Venice to fly home.
It seems like Venice is the most logical place to try to connect to and from the US? Any others work well?