I'm just south of Greenville and my wife works there. Crime in not terrible. The Greenville/Winterville area is just like any other that has a population of around 100,000 full and part time residents. It has it good sections and it has it's bad sections. Fortunately the good sections far out-weigh the bad sections. A realtor once told me that I couldn't ask which are good and bad neighborhoods but I could ask if he would put his mother in a particular neighborhood. I wouldn't put my mother into NW Greenville.
You can also read the daily newspaper at
www.reflector.com to get a little better idea of what it's really like here.
I can't answer your salary question.
The singles life is actually pretty good in G-Vegas. They have a pretty active downtown with some great restaurants and pubs and the City Hotel and Bistro has nightly entertainment. It is a college town after all.