We usually go in to Rovinj because of drinking /driving law. Pula has the best variety for NYE celebrations in Istria.
The business practice of Jayway is one of the worst I have ever experienced.
Coastal route is much better this time of the year.
I would take the bus to Premantura and hire bikes.
You may not be able to arrive or leave Istria by ferry until the end of April, but all the places you mention can easily be visited by public transport. If you ...
Good question Frishki!
Some of the best swimming places in Istria are in Kamenjak nature park and easy to get to by bus, http://pulapromet.com/en/prigradske-linije-eng/
Your plan is all good and you will find best accommodation offers outside the park, https://www.discoverplitvice.com/stay/
Only if you provide long quality videos :)
You may be able to get bus transfer, please give date and time of departure.