I’ve had a ~11 mile (one-way) commute for the last 20 years. Most of the drive is 40-50 mph with a few stops. Carbon buildup has been a non-issue, but I add a can of Chevron Techron or Seafoam to the gas tank once a year. I check the throttle body and clean as required.
A few times in the colder weather there was moisture build up in the crank case. There would be gunk and moisture on the underside of the oil cap. Both times replacing the PCV valve and the occasional longer drive alleviated the problem.
Ed B.