We are spending two weeks touring throughout Croatia. We will be starting in Istria and our last night will be near Plitvice. From there we head to Ljubljana. We have 4 nights left and then fly home from Graz on an early afternoon flight. We will have a car rental. I'm looking for suggestions on what makes the most sense of where to stay. We could base from Ljubljana all 4 nights or could spend the fourth night in Bled. Or on the last full day we drive to Bled, spend the day and then stay in Austria in Villach, Klagenfurt or Graz. So many options to consider. Would appreciate suggestions.
With four days in Slovenia, it would be worthwhile to spend one of those doing the loop through the Julian Alps that Rick describes in his guidebook. You could spend all four nights in Ljubljana and do that drive on one of those days and do a separate day trip to Bled. Or you could do that drive on the fourth day and end in Bled for the fourth night.
There are other good day trips you could take with Ljubljana as your base, depending on what you're interested in seeing. Slovenia is small enough that you can see a lot of it and get back to Ljubljana if you don't want to change lodging. The back-road route from Ljubljana to Bohinj is stunning if you like scenic drives. The beekeeping museum in Radovljica is very interesting. Vintgar Gorge was closed when I was there last year (due to damage during a rough winter), but I visited Tolmin Gorge (which is on the loop drive) and that was some great hiking. The Kobarid Historic Trail is also a great hike, and the WWI museum in Kobarid is excellent.
It's hard to make a specific recommendation without knowing more about how you like to travel and what kinds of things you like to see and do. You're right; you have many options to consider. The good news is I don't think you can go wrong. Slovenia is a beautiful country and wherever you go and whatever you see, you will love it.
We recently drove from Rovinj to Slovenia for a 5 night stay. At 5 nights I found it tough to justify splitting up b/w two different accommodations for two reasons: 1) it wasn't enough time to see the eastern part of the country and 2) bled and ljubljana aren't that far. The one thing we had to make sure to do though was stop at the sites int he Karst region that we wanted to see during our drive to our tourist farm outside of Bled. We had to leave a bit early to get to Skocjan, Predjama, etc. but we were happy with the decision. It was easy to day trip to Ljubljana, and that city is small so unless you're a fiend for cities you can get an adequate taste of it in one full day (it is VERY beautiful though, we loved it). If you plan on doing more hiking and like the out doors I'd just find a nice tourist farm and set up there.