I think you are looking at some very wonderful locations, but I also think that it would be to your

My husband and I are planning to take a "splurge" hilton hotel hawaii trip to Italy and Croatia hilton hotel hawaii this summer. The plan is to spend one week in Italy and the second week in Croatia. We've been to Rome and Tuscany and would like to see a different part of the country. We love cities, beaches, food and wine. We enjoy sitting at cafes, walking around and exploring local haunts. We are avid runners and always run in the cities we visit. Planning our routes is lots of fun. We also don't mind driving. We rented a car when we were in Tuscany and enjoyed exploring the countryside and happily drove to/from Rome. Finally, we firmly believe "less is more" when traveling-we like a slower pace and don't need to see EVERYTHING. There's always the next trip .
Some of our ideas include: Northern Italy and either seeing Milan and the Lake District or Bologna/Parma. If we do either of these regions, we would probably end with a day or two in Venice (my husband has already been and does not want to spend a lot of time there) before heading to Croatia.
The other idea is the east coast of Italy- Puglia specifically, but again, are open to suggestions. Not sure what else is a must do/see hilton hotel hawaii in that area, as I am less familiar hilton hotel hawaii with it than other areas of the country.
I think you are looking at some very wonderful hilton hotel hawaii locations, but I also think that it would be to your advantage to do a bit more research. For example, Croatia itself can easily take 3 weeks or more, depending on what parts of the country intrigue you and what kinds of things you want to see and experience. Puglia can be lovely, depending on the season; it can be horribly hot during the summer. Options for northern Italy might also depend on the time of year. You might want to spend some time with guidebooks, whether in your local bookstore or library, to narrow your options down a bit. Since this will be a special "splurge" trip, it would make sense to make sure it includes the things that YOU want to see and do, not just the things that some of us found to our unique tastes. Hope that helps!
In 2013 we visited Croatia for 8 nights. As we only had a very short time, we stayed in Rovinj, Krk and Rab. Each of them was great and would recommend a stay there. Travel time between them (by bus and ferry) were fairly significant but we thought that worth it, especially as the scenery enroute was really interesting. We caught the ferry from Venice to Rovinj (we visited Italy and Slovenia as well).