Congrats on being accepted into the College Program - you're going to have a blast. I was in the CP in 2010 and was placed in Monorails. So many things have changed since I was there but still hope you find my responses helpful.
Piloting: As far as piloting goes it really depends on the management. Back in the day the CPs were drive trained for the most part, which made sense in my opinion as they could always go seasonal afterwards and fill in during peak times (when I was there there was almost always a shortage of drivers). Since then they changed the seasonal requirements in Monorails from working once every 6 months to 2 months. For some reason I remember hearing they were phasing seasonal roles out of transportation all together, so I'm not sure if that ever played out or not.
Anyway, back to the drive training. When I was there I was told it would be done by department seniority (they would work down the list when you entered Monorails, not by status). However when my time came around they skipped over me and the area manager at the time (who I believe is still there, unfortunately) played favorites and picked who they wanted drive trained, who could stay seasonal, etc. They eventually circled back to me. Not to discourage you, but don't get your hopes up either. I'm not sure where they're at with the new TCS system (aka automation) and how drive training plays into the new system, or how much driving is actually done anymore. While I was there, they did drive train CPs but generally only the ones who had a longer program. For those who weren't, the management at the time let CPs take a train for a lap under the supervision of a manager at the end of their program.
Hours: Pretty much any position at WDW has varying hours. The only thing close to normal hours you will get is a certain time of day, such as opening shifts, mid shifts, and closing shifts. As a CP be prepared as the scheduling department may move you around a bit to fill shifts as needed. Although you don't get to "bid" on your shifts as a CP, generally speaking you will be scheduled similar hours. When I was there I requested nights and the scheduling department at the time was able to fulfill my request for the most part. There were times however when they had to schedule me outside my preferred hours, which I understood and was expecting as a CP.
Best parts about the job: This is sort of hard to explain, but when I was there it seemed like Monorails had a "small town" feel to the department, compared to other areas you could potentially be placed. For example, my friends/roommates placed in other areas dealt with very strict management, red tape, and other CMs looking down on them as a CP. In Monorails the management was great (except for the one area manager) and they very much had an open-door policy. For the most part all the Monorail CMs were great to work and talk with. Same with the coordinators. I did a few shifts in PAC (parade audience control) and the coordinators and managers barked orders and did not come off as the most approachable people. Also with Monorails not being as large as some departments you can be placed in, you will be working with familiar faces. Its also neat to say as a CP that you were placed in a unique role, as very few are placed in transportation and of the few that are placed in transportation even fewer are placed in Monorails. If you do get the opportunity to pilot, its a once in a lifetime experience and there is nothing else like it. I had a blast and miss it very much.
Worst parts about the job: In any role as a CP you may be faced with unhappy guests, but in transportation specifically in my opinion you get more of this. Traveling from point A to point B at WDW can be overwhelming for guests at times and tensions can be high at times. From time to time I also had to deal with guests who would drink too much around the world at Epcot, and would give us a hard time at the Epcot station during park exit. There are also times when Monorails break down at the worst times. My first shift after training, one evening we had to unload guests from a train at an already crowded Contemporary platform, send that train to shop and wait for the next one to come in. While we communicated to the guests often and kept them updated, some could't just understand why we couldn't simply radio for a new train. Also in these situations, your managers are not always readily available to take the abuse from guests. If there is a guest issue they would need to travel from TTC to wherever you are with a guest issue.
Anyway, hope my responses answer your questions. Feel free to let me know if you have any more.