Does defending chokes by tucking your chin in tightly all the time cause an imbalance in your neck muscles in the same way that just doing bench press and no back work would cause your shoulders to pull forwards?
I've noticed that my head is pulled forwards a fair bit and I wondered if I'm just ugly or if I should do some countering exercise that involves pulling the head backwards.
if you are rolling, trust me you are working the back of your neck equally if not more, even if you are defending chokes all the time.
the forward posture is proably a lifestyle thing. try doing a lot of retraction (sit up straight with good posture and bring your chin straight back into your neck, all the while keep your head upright. basically try to make a double chin)do this many times throughout the day.
also keep an eye on your lower back and make sure you have a good arch (that you arent tucking your butt in)
try rolling your hips back.
otherwise talk to an ot or pt to help this. or try to educate yourself and correct the problem.