Originally Posted by
CodyDog
My desire for wider tire potential is based on future trail riding, a little hairier than your average gravel.
If you are really going to be spending more time on MTB trails, I'd look for something that will fit as much tire as you can. A 700x50+ tire, or some of the 650B options. Salsa Cutthroat comes to mind, and will even take a suspension fork. It is 2x compatible even if Salsa currently only sells it in 1x setups right now. The Cutthroat also has a bit more upright geometry than some others which may be good if this is your first foray into drop bar bikes? Sorry, I know this isn't one of the one of the bikes you originally mentioned.
On your original choice of the Checkpoint, when I rode one there was tons of space in the chainstays with the standard 35's. Some have reported 50mm tires fit, but tightly. I didn't see where on Trek's website they said it only clears a 35mm tire, just that it ships with one. What was your source on the 35mm downsizing? I personally didn't pick the Checkpoint due to the weight, my preference for SRAM parts and I didn't like the isospeed on the rear during my test ride. I picked a Warbird V3, and the closest to that is really the Revolt so between just the Revolt and Checkpoint, I'd probably go Revolt.