Sonic from Bravado, he has been so consistent. Dominated the South African scene and is now taking over the NA scene, they haven't lost a match in NA yet. They've beat a lot of tier 3-4 NA teams.
So keep your eye on Sonic, he will make it big one day.
Twistz from Liquid is incredibly underrated, yet in nearly ever event that he attends, he has the highest headshot percentage of any player.
He is likely one of the best aimers in the world but goes very unnoticed.