A few thoughts on the subject -- I used to carry a tent in my RV for my GF who thought it was inappropriate for us to share the RV for sleeping. A couple of places we camped wouldn't permit the tent to be set up near the RV unless it was attached in some way to the RV. So we'd end up with two campsites not next to each other. (She changed her mind about sleeping in the RV when we camped in an area that had a lot of wild Javelina running around getting into everything, including tents!)
Big tents are nice for the room, but if you do 3 or 4 season camping you'll want a smaller tent since they're easier to keep warm with body heat in cooler weather.
Whatever you get make sure you have a rainfly, a good groundcloth and do a good job sealing the seams with seam sealer before that first use. Also most of the tent pegs that come with tents are pretty wimpy, so I'd replace them with some better ones.