Sorry about the broken frame. I have a friend who has an older Carbon Giant road bike he has been dealing with a replacement warranty issue for over a year now - no bikes anywhere. I'd take the 60% off on the SIR, turn around and sell it and put that to a new more agro hardtail if it were me. My SIR is from 2014 with old-school xc geometry, so I overforked it and put a slackerizer (sp?) headset in it to get it a bit more modern. Geometry-wise it is now similar to the new SIR. I rode a buddies Canfield EPO witch is much more aggressive, it climbed just as well as my Niner and was way more planted and faster (fun) dh.Nice. I broke my Niner R.O.S. SS on Xmas day. Niner will give me a 'crash replacement' frame at 60% of MSRP, so I was going to replace it with a new SIR since they don't make the ROS anymore., but would have had to buy new wheels at a minimum (new spacing) and knew I'd end up building a complete new bike and be out $4k, so I'm hard-tail less and no SS right now either, riding my geared full suspension and am getting soft.
What gear are you running, I was 32-19, did 32-18 in Bend for SS worlds a few years ago, but that too steep a gear for our trails here in Boise.
I'm usually a 30x18 or 19 for the local trails at Rocky Point near Portland. The climbs are usually in the 8-12% range so it is a grind (new trails we built this year are more mellow in the 5-8% range). I usually run 30x17 when I go to Bend. The photos from SS Worlds looked awesome, was super bummed I missed it.