The common thread with this build is auto attack damage. Raynor received a noticeable buff to his auto attack damage so this build puts his right up there with the zeebos, kaels and jainas of the world pending you know what you're doing. Goes without saying...in order for this build to work you need to do 3 things effectively.

1) Stay dedicated to your seasoned marksman grind. The talent is only as good as you make it!
2) FOCUS ALL ENEMY HEROES. You are Raynor. You are there to shoot heroes. Do your job full time.
3) Mind your positioning. Raynor has the BEST range & sight in the game. PLAY AROUND THIS.

Last note. The reason you go Hyperion over Raiders is because Hyperion has the same effect on heroes that a typical aoe heroic does. It makes teams play honest. They scatter. Add on the bonus damage you do to forts and structures and this one is a no brainer. You don't NEED to use Hyperion on heroes at all to get full value. Raynor has the easiest time of any hero killing other heroes. You don't need a heroic to secure kills with Raynor. DO NOT hesitate to use Hyperion to take out forts/keeps to push lanes.

On the other hand...the only effect you get from the Raiders is kills. And the raiders can be taken down easily if the enemy team decides to focus them down. Again you don't need the added heroic to do jobs Raynor can do easily with his regular kit.

ALSO this build effectively gives you an out to do full damage with most of the picks made AND get EXTREMELY viable healing at level 7. A common mistake other Raynor users make is thinking they have to choose damage or healing. This build gives you both.