Ability to modify P + PID Position Controller

According to the Multicopter Control Architecture the Position and Velocity Controller Diagram are a mix of P (for position) and PID(for velocity).

Would it be possible to add a PI/PD/PID controller module instead of the P controller for Position?
I note the following codes (mc_pos_control module) have the controllers.
I wanted to know if there are other places to be modified for the different types of controllers.

Any help will be appreciated. Thank you in anticipation!