100 Rated Players:
To make a 100 rated RB, adjust the upper and lower body strength low enough to put all the other stats at 100. Then, fill up the remainders on your upper or lower body strength. You can do the same for a QB, TE, WR, DB, LB, DT, DE. However, for the LB, DT, DE, make sure they are big. For a DT or DE set the weight to 400 lbs. and height about 6' 0". For the LB, set the weight at about 260 lbs. and make him 6' 4".

Simple Tackle:
When on defense go to 3-4 and select "Base". When on the field, choose your outside linebacker and move him near the line scrimmage without crossing it. Once the quarterback snaps the ball, use speed burst to run around and sack him. This will work almost every time unless there is a tight end were your line backer is located.