It rains in Pittsburgh doesn't it? I find rim brakes lost 2/3 or more of their power when I ran through a puddle. In city traffic ability to dodge the blind driver can be important. I like disk brakes almost as much as I liked my Bendix coaster brake. I use 160 mm cable pull tektros, and they have enough power for me + 80 lb supplies on the back. 250 lb up people might do better with hydraulic 180 mm up on long Pittsburgh downhills.
If you were 20 in 1970, you might enjoy bigger tires for hitting potholes, and a drop frame to ease climbing on and off. I got a lot stiffer age 55 and things have not improved since.
Plus with a new bike, you have the chance to get a suspension which smooths out the bumps even more.
If you are going for light weight, look at cannondale & orbea built bikes.
Bikes with mahle geared hub kit are quite light too, although they don't excell at carrying heavy weights up long hills.
I've built the bike left with a geared hub kit on the front. You want a lot of weight on the front if you're going to do that. The kit allows me to buy any brand battery, not a patented single source battery that came from the motor vendor. I paid $630 for the 840 wh battery that is now 3 1/2 years old. I paid $221 for motor controller brake handles pas pickup display. That one wore out in ~4500 miles. I got my money's worth. Installation materials were $80 more. I bought a replacement $740 geared hub motor before the failure, and had it on in two afternoons.
People whine about the messiness of external wires tie-wrapped to the frame. I find having 18" of extra wire looped up on the fork, I don't have to unwire the motor to replace a tube or tire. Just cut a tie wrap & replace it. I find dorman crimp terminals from the auto supply to be 100% reliable, compared to some patented battery contacts on invisible press in batteries.
Have fun shopping or building. Then later riding.
