Nope, you're not nuts. We moved from a 1/2 acre lot and I'm on a little over 6 acres, but if we ever moved back to a subdivision lot (NOT likely!), my tractor would come with me. Just too darn many things you can do easier and faster with a tractor. My thinking is that even on a small lot, you should get the biggest thing you can get that can still reasonably be called a "lawn mower."
If I knew back then what I know now, I would have bought a BX25- or 1025R-sized machine for my 1/2 acre lot instead of a "traditional" riding mower. Yeah, it costs a lot more, but by the time I figure in the cost of hiring out labor to dig out a tree stump, clean up the snow, dig a trench, or whatever, it's probably not all that bad.