About 2 years ago I totally rebuilt my shot. I originally had the one that you grew up with, if you were oblivious to actual basketball without proper coaching, etc. Shot with two hands, and a nasty thumb flick.
Started from the ground up, legs first. Once I got the base of my shot settled I did a ton of form shooting. Would just stand about 3 feet in front of the hoop for hours on end every day building new muscle memory. Did that for a 3-4 months.
Around 2 months into that, I backed up the form shooting to the free throw line and the three point line. I noticed the biggest difference in my shot going in when I started doing that from the 3 point line.
But now as I play mainly with friends in semi-competitive games I find myself drifting back into my old habits.
Rec season is coming up soon so I will probably start doing some drill work again just to get the correct feel for my shot once more. I played a lot over the summer and made 56/100 3's one afternoon just by myself which is good by my standards.
Would be cool to get a Boneyard basketball league going haha.