I like the Kona Rove ST, but if I went with a bike of that nature, I would without a doubt go with a BMC monster cross disc. I still might, once they restock in the fall (they sold out almost immediately), but the bike isn't meant to handle a load like the 920 and Sutra. My wife says I need two bikes. Maybe she's right, but I don't like taking care of two bikes. I take care of two bikes now. Mine and hers. If I got two bikes, I would be taking care of three bikes.
While Mike has said the monstercross isn't designed to be a touring bike, I converted my rim brake model to commuting/touring and its been great.
The heat treated OS tubing, at 8/5/8, is plenty stiff and strong. The bike"s geometry lends itself to be stable when loaded and the front fork handles a rack and panniers just fine.
Yes, an intended touring bike will have thicker tubing, typically.
I am 220# and ride the 65cm frame. Me plus gear is heavier than what a lot of others will have on the bike, and my frame triangle is larger than any rim or MCD triangle, so if mine feels fine then smaller frames won't flex as much.
Just offering up some thoughts since you mentioned the MCD.