Planning trip from Greece to italy - Slovenia - Croatia - Serbia - FYROM
 

I am planning a trip this summer, the first outside my country Greece. I have posted a similar post to advrider but i had very few answers and not the ones i was hoping for, so i thought to test my luck here.
So the plan is to leave Igoumenitsa Greece by ferry to Venice Italy, and then on travel all around Slovenia - Croatia for a while, see the sights and then return via Serbia-FYROM.
My main concern in about road conditions, accomodation and safety.
I also want to know if i must make accomodation arrangements before i go there (iam talking about Slovenia Bled, Ljubljana and Croatia Plitvice, Dubrovnik, Split) or i can easily find something there on the spot.
Finally any suggestions of places to visit, especially those off the beaten track are always wellcome and even better if you could give me any suggestions about routes to "must-see" places in these countries. The trip hopefully will last 15-17 days so it is enough time i thing to get a taste of the scenery and life there.
Looking forward for your answers.

I moved this post to a more suitable place, please someone delete it