Bike shops I've spoken with report that if someone's planning on having just one mountain bike, increasingly it's a fat bike. In Eastern Ontario where I live, this is definitely a trend because it lets you squeeze more fun out of winters that are becoming more unpredictable for freeze/thaw and snow.
Fat tires are great in snow and other soft conditions, but are overkill for summer riding. One solution is to get a second set of wheels with a narrow rim that let you run 3" tires. This combo can shave a few pounds off your wheels compared to a standard fat setup. More importantly, reducing the rotating weight improves handling and acceleration, making a ponderous fat bike feel almost sprightly on summer trails.
This is a wheel set I'm offering as a solution. Hubs are the excellent DT Swiss Big Ride, running 150mm x 15mm thru-axle in front and 190mm x 12mm thru-axle in the rear. The rear hub is easily converted to 197 mm wide by swapping optional end caps, and both Shimano and SRAM XD freehubs are available. Note that in the picture the front wheel shows a centre-lock disc brake mount and the rear an ISIS (6-bolt) mount. ISIS mount will be standard on both.
Rims are DT Swiss XM481, which is a robust yet lightweight option for all-mountain use. Spokes are DT Competition butted with ProLock aluminum nipples. Wheels are tubeless-ready.
For more information and pricing, contact your local bike shop, e.g. Rebec & Kroes or Almonte Bicycle Works.