I just went to 2 x 10 and climbing is just as easy. All the climbs are way easy at redwoods anyway except direct rd and frontal lobotomy but I managed both of those with a taller geard 2x10 setup than I have now on my current bike (was on a borrowed bike last time I rode there) and I'm a pie eating fatty
More off the shelf bikes should come with 2 x 10, 3 x 10 is just dumb imo
I have 2x10 on my newish GT sensor 29. Spend most of the time in the small front chain ring - use the large mostly on road and 4wd tracks. Climbing is just as good as 3x9 on my old 26" hardtail, bit harder to compare cause of weight difference between bikes but i find myself worrying less about the front gears and just concentrating on the rear.
if the 26 sensor is anything like the 29 then its a great bike.