Going through FCO twice...indeed! That did create a logistic problem, but I argued that I was transiting FCO on the outbound, then the inbound journeys, Bari (BRI) being the destination. I believe that is the only way that you can transit the same airport twice on a routing of this nature. Please tell me if my reasoning is flawed.
As a British driver used to a well-ordered sense of road usage (in Britain, Switzerland and the USA for example), I found Sicily curiously easy to adapt to. The long distances and highways present no problem; the cities are more chaotic, and can be stressful. Waiting at a junction to join a busy suburban street in Palermo is useless, for example: you just have to push your way in, and they will let you in. It's all about give and take, and there is often no sense of give in other European cities. The tooting is rarely the horribly aggressive act it can be elsewhere.
I've always admired the Italians for the quality and skill of their driving, and I find if you emulate them there is no problem. What seems like chaos often has a sense of order and flow to it. I did see one accident by night on the long south coast road, the E931, only parts of which have been upgraded. I would suggest avoiding night-time driving as there is a goodly absence of road markings on the roads other than autostrada: that combined with trucks makes long distances by night quite tiring. The Michelin map 932 is good, but oddly, quite a few of the roads marked on it haven't been built yet.