OK! This one is becoming easier everyday. The advatanges are the same for the small, medium and large markets. You'll be the only one. That is, if you're the morning drive guy. You could be one of two if the station ownership feels they need a 'live' afternoon drive person, too. The disadvantages...they don't need on air talent because they're satellite fed 24/7. In which case you still may be in luck, since the FCC requires stations to have two full-time people on staff, you'll still have someone to keep you from getting lonely.
It reminds me of a cartoon I saw many years ago of a guy sitting at a huge radio console. It had only one switch on it...On and Off. Sitting next to him was a dog to keep him company.
I can remember the days when we had live on-air personalities 24/7 and broadcast engineers at the transmitter 24/7. The on-air people were well-known in the community, the stations were part of the community because they were locally owned and operated. You could walk through the front door and talk to the owner. There were news staffs that covered local news all day, every day. They had people called 'music directors' that selected the music for that station based upon what listeners wanted to hear.
How things have changed. That cartoon was from the 1970's, but it forsaw things to come. Now we have conglomerates that own several stations in a market; carry little, if any local news; program what they want the listeners to hear; have no one with authority to make local decisions; and their on-air voices for all their stations are 'piped-in' from some other part of the country.
A local group owner, where I'm located, has 5 radio stations. On the weekends, there's one person to oversee all 5.
I'm just glad, over the years, to have worked with some great people who loved radio, were good at it, and gave me the opportunity to be a DJ, when being a DJ was cool.