The biggest worry for me is body joints, and hips.
Wrists and elbows are tied for most damage, fingers second, and hips a very close third. Knees, and ankles take up a solid fourth place.
I've broken my collar bone but no jacket on earth would have stopped that.
What I'm getting at is I can not see the value in a complete armored jacket. Same for pants that protect your thighs, and shins.
If I were completely naked, and had to choose what to protect, it would be the parts I have listed, and hurt over, and over again. Track days... sure. Race weekends where speeds will be insane... sure.
Riding to the store for rolling papers, and porn mags... not so much
Riding armor reminds me of my daughter. She came home one day with a hickey on her neck. Putting on my best "daddy" face I asked where she got that?
"I was running up the stairs, and Jen tripped me from behind". Now I've fallen up, down, over, and across stairs but NEVER ONCE landed neck first.
not to sound ignorant or falsely brave but knee pads, wrist pads, gloves, elbow, and hip pads are all I feel you need. Those, and a good pair of boots.
If riding sucks that day? You're ready for hockey or kung fu.