well if you built a combo CB, you cant really make him into a man specialist because of the funky ALGs (auto level gains) that combo CBs get. combo CBs are good for making blitzing CBs, but thats about it. if you really want a man specialist, retire and go with a man specialist CB. however, if you want to keep him, there are two roads you could take.
1. go with a blitzing CB build
and
2. try to make him into a man specialist with the ALGs you have.
if you go with route 1, power tackler, ball hawk, pass rusher, and then maybe clutch, or jump the snap and or streaky.
if you go route 2, there is ball hawk and football genius. both of those are kind of shoe ins. clutch, 3rd down stopper, and long reach are ones you can choose from for your 3rd and 4th VAs.