Oceanside can either be really nice or really ghetto- depending where you live. The more well-off people tend to live in Ivey Ranch, Mission Mesa, Fire Mountain, Ocean Hills, and the homes near the El Camino Country Club. As for Deep Valley, Eastside, South Oside, or Tri City...well, those are the areas you want to avoid late at night.
Oceanside is actually very beautiful, and contains a nice community college, MiraCosta, an old drive-in theater in The Valley, a country club, a bike trail, a mission, and several bars and businesses along Coast Highway. Great place to visit.
Let's go chill in Oceanside, CA. There's always something to do out there.