Croatia itinerary

You have a sensible itinerary from a logistical perspective, but it is very rushed. If you're okay with 1-2 nights per location, I think it's fine.

There are a number of other places to consider, but not if you want to include all the stops you've already got. The drive over Vrsic Pass is stunning as is the back-way route from Ljubljana to Bohinj (via Škofja Loka and Železniki). The beekeeping museum in Radovljica is also delightful and informative.

By the way, the highways in Croatia and Slovenia are excellent. Hire a driver if that would be your preference, but when you say "brave the roads," you should not be concerned that they are in poor condition or have horrendous traffic. One suggestion I have, though is that you ditch the car in Split and travel via ferries to the islands and to Dubrovnik. You will have no need for a car for that portion of your itinerary.

I agree with the previous poster that your itinerary seems a bit rushed. I suggest some modifications as follows. After researching quite a bit, we kept coming up with the information that Hvar was notable for a big party scene. Not our thing, so we scratched it.

Plitvice is apt to be very crowded in July, so you should spend the previous night nearby, in order to get there early. Driving from Plitvice to Split, with a stop in Trogir, would give you very little time to see either town.

I found driving in Croatia to be very easy. Roads are new and in good condition. Other drivers were courteous. No reason to think it requires "bravery." I, btw, was over 70 when we did that trip.

I like Istria a lot, but I sort of feel you'd be better off dropping it from this trip to allow a bit more time elsewhere. Ljubljana, for example, is certainly worth more than being a stop on the way to Bled. I'm glad you have two nights in Zagreb, whose large historic district I find both attractive and lively. Plus there are many interesting museums.

I took buses through Croatia and Slovenia in 2015. Certainly, that is not the same thing as having to drive, but the roads didn't seem problematic to me. I do remember a curvy two-lane (but not mountainous) stretch on the way from Zagreb to Plitvice. Inland Istria is probably somewhat similar.

Do heed the advice about spending the night in Plitvice so you have some time there without all the day-trippers.

I'll repeat here what others have said on this forum, though I have no personal experience with it: Many of the lodgings on the Croatian islands have 3-night minimums. So it might be worth checking on that early on, just to see whether your favorite hotel website (I use booking.com) shows very little available for 1- and 2-night stays.

If you have the (big) budget, I suppose it is possible, but there is no need for a private driver, as the bus/catamaran could get you between most of these places (though there would be some snags). However, the pace is problematic to me--is this how you usually prefer to travel? It will be hot and high season--I would slow down. When will you even have time to do laundry?

A moderate pace for your itinerary is 3 weeks.......

Most accommodation on the islands has a 3-4 night minimum stay, so pick either Hvar or Korcula and stay 3 nights.

I would consider dropping Bled and Ljubljana, as you don't have the time and it's out of the way. Two nights somewhere is only one day, with the amount of travelling that you are trying to fit in.

Plitvice will be busy, so it's sensible to stay the night before. Allow 5-6 hours at the park and Split is then a 2.5+ hour drive, so a full day. Split and Trogir deserve a full day each

Rovinj really needs 4 nights and ideally a week.

Driving in Croatia is easy and you don't need a driver, as the roads are good.

Sorry, I just have to take issue with this statement:

Rovinj really needs 4 nights and ideally a week.

Everyone travels differently. It's one thing to offer advice as requested by the OP. It's another thing entirely to impose our personal preferences on others as if they were established truths.

I spent three nights in Rovinj. I pretty much got the full experience of the town in one day. The next day I spent on a road trip exploring Istria. You could certainly stay longer than I did and see more, and if you have a week you could probably enjoy yourself with sightseeing and also have plenty of time to relax. But many of us have spent far less than a week in places like Rome and Amsterdam and London and Paris and had wonderful experiences there.

I would hope no one on this forum would ever be dissuaded from visiting any destination because they were told it "needs" more time than they have. We all have the choice to squeeze as many different experiences into our time or to allow ourselves the luxury of a relaxed and laid-back travel experience. There's no one right way to do it. The OP says she's been traveling independently for over 20 years. She clearly knows what the trade-offs are.

And Laura, you asked about places not to miss. The answer is that there are no places not to miss. When I was planning my trip to the Balkans, I originally hoped to spend a few nights in Zagreb. In the end, I cut Zagreb from my itinerary because there just wasn't enough time. I had a wonderful trip and didn't think about what I missed by not going to Zagreb.

You will bring back wonderful memories of the places you visit. None of us can see everything; the point is to take pleasure in what we see.

I think your need is very simple. A ordinary itinerary may suit your purpose.
After reading lots of itinerary of Croatia and Slovenia, I have got a pattern.
Have you brought the air tickets? If not, buy a one with Ljubljana in and dubronvnik out.

day 1 Fly to Ljubljana
day 2 Ljubljana stay in Ljubljana
day 3 go to Lake Bled and stay in Bled
day 4 Bled stay in Ljubljana
day 5 Go to Postojna caves and Skocjan caves than go to Croatia boundaries
stop at motovun and stay in rovinj
day 6 rovinj stay in rovinj
day 6 rovinj to zagreb, zagreb to plitvice stay in plitvice
day 7 plitvice all day stay in zadar
day 8 zadar to split, have stop in sibenik
day 9 split stay in split
day 10 spilt to hvar stay in hvar
day 11 hvar stay in hvar
day 12 hvar back to split then go to dubrovnik
day 13 dubrovnik stay in dubrovnik
day 14 montenegro day tour stay in dubrovnik
day 15 departure at dubrovnik airport and say goodbye to Croatia
This is the skeleton of a normal croatia slovenia itinerary. You can add or subtract to make it as your own one.

I don't undertand the point of traveling from Rovinj to Plitvice Lakes National Park by way of Zagreb if you don't have time to see Zagreb (which I quite like). It's wildly out of the way. In that respect, the original plan looks better to me.

May be you need to spend one more day to visit zagreb.
The itinerary is just copied from some travelling agents that operates tours of Croatia, Slovenia and Montenegro. As you know, the itineraries from travelling agencies are always in a hurry. However, the main direction of planning is correct.
I need to recap: please add and subtract to make your own itinerary. This itinerary may not be good for everyone.

This is the itinerary of mine. I have brought the airtickets and booked the hotels.

day 1 arrival to split stay in hvar
day 2 split to hvar stay in hvar
day 3 vis and blue cave, stay in hvar
day 4 hvar to brac, brac to split stay in split
day 5 split to zadar, stop in sibenik and krka, stay in zadar
day 6 zadar to plitvice, stay in plitvice
day 7 plitvice to zadar, stay in zadar
day 8 zadar to pula by air croatia, stay in pula
day 9 pula to rovinj, rovinj to porec, porec to pula, stay in pula
day 10 pula to labin, labin to pula, air croatia to zagreb, zagreb to dubrovnik (only 3 hours in zagreb airport, not going to the city centre), stay in dubrovnik
day 11 dubrovnik, stay in dubrovnik
day 12 montenegro tour, stay in dubrovnik
day 13 stay in 5 star hotel in dubrovnik, not going anywhere
day 14 back home

I use air croatia to shorten my travelling time. But I scarified all the places in slovenia as well as the capital of croatia. This is my own choice but may not be yours.

Thank you everyone for the information. I have decided to travel to Croatia at another time , too rushed for time this year. I found a low airfare to Copenhagen so I'll be heading to points north for two weeks. I'll seek advice in that forum. Happy travels all!