If you don't need the bed up above and climbing up more stairs getting in the rv is not a issue for your health (knees), then I would consider the class a. While there are some c's that you can get with the entertainment center in the place where the overhead bunk usually is, most of them have that bed there of course if you are planning on grandkids going with you, then that bed space is good to have. Class c's generally sit lower to the ground and normally have less steps to get into.
Class a's captain chairs normally swivel and are usable space. Most class c's are not. You will also generally get more outdoor storage with a class a. If it was just wife and I, we would have a class a.