I used to do a long part bus/ part bike commute. I really favored the biking part, even if it was raining. My strongest aversion to bus riding is that they feel like virus pits. Second, is the freedom of transportation with a bike. You can go where you want. If you need to do errands, no problem on a bike. Third, I'd just rather be moving. Waiting bothers me. I feel like I'm getting no where.
There are pluses to the bus. The one that comes to mind is reading. If you need to study then busing can be a good use of your time. When I was a beginning programmer, I'd often spend the ride to and from work reading books on Fortran to solve coding dilemmas and figure out what I would be doing next. And they are a bit drier in the rain.