Thanks djb, read a lot of your posts lately!
Apparently 48/36/26 and 40/30/22 are the only two options exists now in 3x10 Shimano line, or Hollowtech line at least. So either too high or too low. I guess I would try to go with 40/30/22, big ring should work for unloaded touring, and other two for loaded/climb parts. Or maybe the middle ring will work for unloaded too, will see.
Regarding shifters, I've used to STI on my cx bike, but in this build I want to go with Microshift bar end shifters because of simplicity of the design (Cowchipper handlebar is on my mind).