I think it all depends on how you use it. If I was going out for a month or two at a time, I'd want my nice big motorhome. I plan on doing that someday which is why I keep my 35 foot DP. But if I were a weekender and mostly going places with hookups, I'd be fine with a smaller RV. The need of hookups is the main thing for me. My 35 footer carries 100 gallons of water and I've got a 2000 watt inverter so I can travel all the way cross country boondocking in Walmart parking lots and live on the water and power I have. Many smaller RV's only carry enough water for a day depending on whether you like taking showers or not. That would be the biggest deciding factor for me. I want an RV where I can be self sufficient for at least four days and be comfortable.
Now I have heard that they are putting bigger tanks in smaller RV's, but I haven't looked in a while so I don't know where they are with that.