Have you traveled at all in an RV? If not, I strongly urge you to consider renting a Class C and taking a short trip to a local campground at first to learn how to operate the equipment and see if you like the lifestyle. If the first trip works out OK, take a much longer trip. After that, you may know if you like the vagabond way of life and are still willing to put out a lot of cash for your own rig.
If you know at now RVing is what you want to do, take some time to evaluate what chassis and floor plan works best for you. Take in some RV shows. The biggest in the country is in Hershey PA in mid-September, and it's not too far from you. They have many rigs of all classes on display. Examine floor plans and build quality. It can take several days.
You noted in your post that you are interested in traveling across the country and perhaps other long trips. You will need to plan to carry a fair amount of stuff with you. Therefore, you should consider a rig with a high OCCC rating. In Class C rigs in particular, it's not how much room you have as much as how much weight your rig can carry safely. This is very important to consider IMHO.
Things that decrease your OCCC are length of RV, and some options like slideouts and automatic levelers.
There are many opinions out there, and these are mine. BTW, we have traveled across the country twice, and up to Alaska once in our 27 foot, 2011 Class C. Best wishes for success in finding the rig that is just right for you.