Welcome to the forum.
I can't give much advice on class C's since I've never owned one (our first RV adventure was in a rented class C). I agree that the cost of a TT and tow vehicle together can rival the cost of a class C. That said the tow vehicle can be used as daily transportation. Not so much so with a class C RV. The one drawback I found with a class C is that unless you're going to tow a small vehicle behind the class C you're going to have to rely on other transportation when you arrive at your destination if you plan on doing any sightseeing in the area. Either that or have to disconnect form campground services to use the class C as transportation every time you want to venture out.
Beyond that, enjoy the hunt and I hope whatever you end up with you and the family get to enjoy many hours of traveling and camping together.