Look at Surly Bikes,,just for some ideas.
I ride a Surly Ogre,,with front rear panniers,fenders/mud faps.
50 622 tires( 28 in Europe) flat bar disk brakes,,no front shock,,rigid fork.
Real comfortable

Or would save a bit more and get the Rahliegh Sojurn.
Cross bikes. I had to much toe overlap on front tire with fenders.
While doing cornering and pedaling.