I spent a lot of time in Croatia and Bosnia during the war. The people are the greatest, they treat you just as if you are family.
If you are going into Bosnia, I have some people that you could stay with.
In Croatia the very best place to visit is Dubrovnik. It is a walled city and the architecture is some of the finest in Europe. Most of the damage from the war has been repaired.
The temp over there is very much like New York at the same time of year. Cold in the winter, but hot in the summer and spring and fall about the same.
There used to be offshore racng from Italy to Markaska on the Croatian coast in the 60's. Great open ocean running across the Adriatic all the way.
Give me some more ideas on where you want to go and I'll see what I can do to help.