I don't mean this to be derogatory, but it sounds like you are looking for someone to convince you that you need a Class A.
What you need can only be defined by you. But as with all other such questions, often found on this forum. Follow the advice that is readily available here.
Make sure that you drive and even test camp whatever you think you would like. If that means renting the unit, so be it. And then follow the advice about purchasing and checking out the unit, if you decide to go that route.
If there is nothing seriously wrong with your Class C, then most of the items you listed, could probably be relatively easily updated or modified. It depends on how much money you are willing to part with.
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