Infinite player creation points
Create a new player, and then select the edit-player option at the roster screen. Select the newly created player and press right to get to the speed option. Press X, then press X again to unlock infinite creation points.

Various end zone celebrations
Hold down one of the following button combinations right after scoring a touchdown to perform the desired celebration:

Hip thrust -- L1 + square
Spike the football -- L1 + X
Jump spike -- L1 + circle
Say a prayer -- L1 + triangle
Slam dunk -- L1 + R2
Shoulder shake -- L1 + R1