We live in downtown and there are pockets of gang areas throughout Oceanside. Not big like LA, but they're still there.
Usually we get the loud music cruisers and gang writing around. It gets cleaned up and comes back in a short time.
Downtown is undergoing major redevelopment. Still has the usual marine services and some good projects underway. The marine presence makes it easy to walk around at night.
The cops are aggressive in downtown. It's near the beach and where the tourists come.
I've lived in Pomona, south Sacramento and Fontana. I'll take Oceanside.