My biggest concern would be navigating the sometimes narrow European streets with a Class C. Do the countries you want to visit allow a "towed" vehicle to be used for site-seeing? It would be much easier to park the RV and use a smaller vehicle to check out the sites. From what I remember larger vehicles such as trucks had a much slower speed limit than automobiles, does this apply to a Class C RV and if so have you factored that into your travel times?
Not trying to discourage you, just want to make sure you're prepared for the journey.
Doug