I was searching around for a comprehensive list of the different skill upgrades that become available in road to glory but couldn't find one, so I figured we could start one here.

Post some of the more rare ones that you have seen.

The rarest one I've seen is this one.

DTM:
Cost 34464 points
Rarity Level 5
Career Boost
Agility to 99, Speed to 99, Acceleration to 99