Don't go 1x for a tour like that! You're going definitely going to want some lower gearing for the terrain/length of tour. I'm in the midst of swapping out pretty much everything but the brifters and front derailleur on my gravel bike. A few youtube videos and a bit of swearing later, I'm a much more competent bike mechanic. It's not as daunting as a task as I thought it would be.