Trek opinion
I have the Trek you are considering. It seems quite capable as a road bike ,mine wears Maxxis Re-Fuse road tire in 40 mm, with tubes at 50# it handles cracked roads, chip seal, clay and light gravel, and even the occasional horse trail for myself and gives up very little to a dedicated road bike. I personally prefer the two chainring system over the one. I find it easier for me to find the just right gear for me as I can lessen some of the jumps .Don't be to worried about the aluminum vs carbon thing. I have a newer carbon Domane shod with 32's and the Checkpoint is a lot smoother overall. with the wider lower pressure tires. Some may argue but I consider aluminum more durable for thrashing around in the rough stuff . I wish you luck in finding the right bike for yourself. I find myself grabbing this bike quite a bit more than I had expected I would. Just wanted to give you a review/opinion of one of the bikes you were considering. It just seems to make me smile.