HEre is your task. Make Kevlar patches for ass and knees. With mesh everywhere else. It would sell.
I am putting together a 25 mph mid. And, after not being on a bicycle for a while, THAT IS FAST. And so, protective gear is a good thing.
Oh, I KNOW FAST. I have a VERY racy R1 that is 65 lbs lighter, two teeth up on rear, pipe and air. Grunt like only a ducati knows.
I designed a iron in Kevlar patch to your existing mom jeans. I had to flee, before I got it going, but will again soon. The trick, will be keeping the Kevlar patch centered. Maybe a ring all the way around the knee. And a stirrup.