A way of progressing the pallof press can be achieved by adding an instability element to the pattern. This can be achieved pop using a small weight that you thread the band through. A quick pressing movement and a concerted effort to stabilise the long arm position increases the load into the trunk. This is a good way to toughen the exercise without just putting more weight on the exercise.
Punch directly in front of you
Drive heels into the ground
Grip the band tightly
Pause slightly at the arm extended position
Targeted muscles trained
Posterior deltoid (outside arm)
Key movements trained
Rotator cuff co-concontraction
This variation is less about the load and more about being able to absorb the perturbations and turning on your stability producing muscle quickly and effectively. This is an issue that can fly under the radar in those with a history of back issues. If you do have a history of back pain or injury then this exercise needs to be respected and built in to.
The same can be said about the rotator cuff. The fast movements that create the instability at the end of range also needs absorbing from the shoulder joint, therefore using it in the reconditioning of the shoulder can be justified.