Yeah last week at NCY I was looking at riding gear - and got the sticker shock on helmets. Anyway they had a line of really cool looking jackets with body armor on the back and arms/elbows. Not super heavy with good ventilation. I'm a guy who sweats alot...perhaps more info than needed here
Good gloves and some boots are also mandatory.
Edit - drinking wine again. I want really good protection but back in my day protection = leather. Here in SoCal that can get really hot. I've seen some new synthetic jackets with body armor that looked really nice without the leather look. Anyone with experience on this stuff? Sorry I don't have the brand names in front of me, and on glass #3 of wine I don't have it on the brain either.