My recommendations are:

-lose the cheap red dot and get an Aimpoint Micro H1. 5 years of battery life, bombproof
construction. I had the same red dot you have, it could not be trusted to hold a zero or even turn
on.

-lose the forward grip/mag holder. Work on shooting your support hand all the way out with your
thumb pointed forward at the target like you should or are doing with your pistol stance.

-if you must have a spare mag on the rifle, get a Redi-Mag

Otherwise, your most pressing need is a carbine class.