We are flying into Budapest for 3 days in the middle of April (4/18) and then on to Croatia by bus? Have reservations in Zagreb 2 nights, Split 3 nights, Dubrovnik 4 nights and then on a small boat cruise for 7 days 4/30-5/6, then flying home from Dubrovnik. We want to add Slovenia specifically Ljubljana and maybe Lake Bled or Plitvice National Park, changing the amount of days reserved. How reasonable is this itinerary, and recommendations for which destinations to change? I am concerned about the weather on the cruise but unfortunately we cannot change reservations. Any help would be appreciated.
Four nights is rather a lot for Dubrovnik, quite a small city.
Plitvice Lakes National Park can be visited between Zagreb and Split. There are buses to the park from both cities. The key thing is to spend one night in or near the park so you are not part of the mob descending on the park during day-tripping hours. The crowds seriously degrade the experience. (Google for photos of the park and you'll see what I mean.) There are one or two hotels at the park (overpriced due to their location, I gather), plus other options outside the park, at least some of which will pop up on booking.com. I haven't checked myself, but I think you might find a few places either close enough to the park to walk (but you will probably be walking along a country highway without sidewalks) or offering some sort of transportation to the park. Or you could rent a car for just that part of your trip, of course.
I liked Ljubljana. Bled is a small town, and you can walk all the way around the lake in 2 hours or so. To me, Ljubljana makes a better base unless you have enough days in the area to allow explorations to Lake Bohinj and beyond.
You could take the train from Budapest to Ljubljana, and then go on to Zagreb quite easily. Ljubljana is a great small town. One night is enough, maybe 2. Going from Zagreb to Split by bus, you could certainly go thru Plitvice, as it is right on the way.
I love Slovenia, but I don't think you have enough time to do it justice on this trip without rushing through the rest of your trip. You'll need at least two nights to make it worth the trouble of taking a long train or bus ride down from Budapest, and even that gives you only one full day there. Really you need three nights to justify the stop there in my view. So where will you cut out three nights from your existing itinerary? Plus the stop in Plitvice?
I'd save Slovenia for another trip so you can see Croatia in a more relaxed way. Stop in Plitvice for sure.
I will be in Croatia in April also. I have found, or not, as the case may, be that busses are not as frequent as one would like to plan an itinerary. To go to Plitvice as a stop on the way between other cities does not seem to allow an optimal stay.
Many of the bus times seem to be either early mornings and then not until at least 3pm. Nothing in between. This for many cities in Croatia.
I hope when I am there things will become more apparent, but presently from home, the busses look like my planning will have to wait until I am there.
I've never had great confidence in the accuracy Balkan bus schedules found on the internet. The best thing to do is go to the train station and ask there. Back-up plan is to ask at the local tourist office, which in my experience sometimes picks up the phone and calls--something few of us have the linguistic skills to do ourselves.
Keep in mind that day of the week can be very important, and seasonality can be an issue.