I make EXCELLENT money in a small ED, but you need to decide if it is for you or not. I work in a very small hospital with a 7 bed ED and 2 nurses. No allied health staff and no specialties except for one general surgeon in town. It is almost entirely staffed by mid-levels except for the time one of our supervising docs comes in to fulfill his supervisory requirements (which usually consists of us sitting down for coffee and talking about the weather), or we call them in for something (very rare). They are very good about making themselves available over the phone, so you do have someone to rely on, but you can't be calling them for every patient.
We are also about 80 minutes by ground away from the nearest tertiary care facility, and that's driving like mad. If it is something bad (we have a lot of major traffic accidents), they bring them here for me to stabilize and we have the bird come in to take them.
I would definitely recommend previous experience in Emergency Medicine in some capacity. I was a Paramedic for several years before I went back to school, so EM seemed totally natural for me. If you like being able to really practice as an EM PA, you would love a rural ED. If your vision of Emergency Medicine involves staffing a fast track area, I would suggest you move on.