I recently went back and forth between a Surly Crosscheck and a Novara Randonee (officially, a “CX” bike and a “touring” bike). Honestly, they were so closely matched that it really was splitting hairs to talk about the differences. The ride was virtually identical, and the biggest material differences between the two are easily changed, i.e. tires and shifters.
What it came down to in the end (as it usually does) is how the bike fits and feels to you when you test ride it. The CC was a 56 and the Rand a 55, but the stand-over height on the Rand was lower enough in comparison that I just felt like I had more control over that bike. I forget the exact difference of all the frame dimensions, but I just remember thinking that the CC felt bigger than it’s measurements suggested. The more I went back and forth between the two bikes, the more I felt at home on the Randaonee, so I got it.
So just pay attention to fit and feel first. It won’t matter if your bike can plow through four inches of mud, or carry 40 pounds of camping gear, if it’s too big or too small to commute on comfortably every day.