Have you ridden a Kona? They feel small and nimble. My next bike will probably be a Kona 29er - feels like a 26.
Have had 2 Konas. The last 26er I owned was a Kona. And the first 29er I owned. But I don't think they're making a 650b dually (?)
(edit): just realized they do. Will take a look.
The current and IMO right Kona's have the ride in it vs on it feel in two wheel sizes, hard way or soft.
Some new Treks are that way, and have a super new shock if you've enjoyed aspects of a hard tail, they are firm when you pump them.
Wade, Tim and I have three different versions of the modern Konas. Chad has the 2015 Remedy with the new shock tech and Derby rims.
What's cool about the Trek shock is its firm when you want, and not the on off firm or soft like VPP or DW yet it's totally free open or plush when it takes hits.
Some of the new Treks have double or triple chainrings and that's unfortunate.