The 26" with a 47mm rim and a 2.6 Gazz will be far more user friendly for single track than the 2.3 Stout. If there were a 29er Gazz 2.6, with the same rim widths, then they’d be very similar similar.
I have the KH 29 with a Stout and I sold it because it did not handle as well as my 24" muni with an Intense DH 24x3. Part of the problem is the increase ride height, but it really comes down to tire volume and profile. The Stout is a mtb tire, meant to be ridden in pairs, so it’s really not that wide if your coming from the Duro Wildlife, Gazz, or Intense.
Though the Stout is one of the highest volume 29er tires, it doesn’t absorb surface variations, rocks, roots, etc… enough to be considered a muni tire. I’m not an expert rider, but I’m a solid intermediate, and I felt like the 29er with a Stout made everything at least one grade harder, at times kicking me off the uni in places where I cruised through on a 24.
I have ridden a 26" with a Gazz 2.6, it was a good ride, not really sure why I sold it, but it was a good compromise between a 24" and a 29". The 26 rolls obstacles better that the 24, still tech worthy, not noticeably heavier than the 24. Many people believe the 26 is just too close to the 24, but I noticed a significant difference.
I will be getting a KH 26, but I’ll set it up as a lightweight ride, 2.5 single ply tire, ~38mm rim, light cranks, Ti hub, carbon seat, etc… My 24 will remain my workhorse muni for the nasty stuff.