I don't know what road surface your touring will include, but a fat bike would be for touring where there is no path yet. Across deserts, forests etc.Any tour with some sort or path can be done with 2" tires and wide rims. I have 2.15" and 30mm ID rims upfront of my Toughroad and it is comfortable yet fast rolling. You can get touring tires up to 2.35"...
The fat tire with off-road profile is great for "no path touring", but will cost you significant speed everywhere else.