Not sure what's meant by "long sleeve kevlar and body armor."
This was covered in detail in the "alternatives to jackets" thread. You're most likely to hit your elbows, forearms, shoulders and back. If you get armor that covers all of that you're basically wearing a jacket anyway.
Been shown over and over that leather is THE choice for abrasion resistance.
Kevlar:
Leather:
Link to original page on YouTube.
MotoGP riders have access to essentially unlimited funds (at least from our point of view) when it comes to protective gear. They wear kangaroo leather suits. Not that the conditions on the street are anything like those at an FIM-approved track... the point is that if alternatives were better, they'd be showing up at the track. They aren't. Take that for what it's worth.