There really sin't one bike that will do everything really well. The multi cylinder bikes shine at eating up mileage with comfort and speed, but they aren't as much fun as a thumper in technical stuff. Kansas is kind of an outlier, from a terrain standpoint. I've ridden out here for a couple years now, and I haven't once come across something I consider technical. You can drive a jeep or a truck down everything we ride on. For me, technical stuff is, bar width trees, difficult climbs, sketchy descents, etc.. stuff where its a real challenge to break 20mph. That doesn't really exist out here.
Having said that, I have more fun on my little 530 than I did the AT, but the AT is much more comfortable over a long days riding. I like riding a 'slower' bike fast, over riding a 'faster' bike slower, if that makes sense. The AT did really well for its weight and what it was built for, but it just physically can't handle and react to terrain the same way a 250lb single can.
Cliffs notes- get several bikes if you can, lol.