Of course being able to place shots is a top priority. "You can't miss fast enough"
I have a S+W M+P 9C and a Shield Plus. Pretty similar. The M+P 9C is wider and fills my hand better. The Shield Plus is lighter and narrower . Better for concealed carry. Its shades of grey. At 5 feet in a panic I'd choose the gun I had on me.
At 50 feet I might shoot better with the M+P. At 50 feet I might be better off to escape.
I'm not a fan of the Dremel grind,reshape,and stipple routine some do to polymer frames. Thickness of wall section matters. Failure is not as option but it could happen.
What I have done is make "adjustments" If I have a muscle or tendon moving the frame during a trigger squeeze, Yes! I will use a scraper to judiciously relieve a minimal amount of material . If an outside corner is making a noticeable pressure point on a knuckle or finger, I'll soften it just a little. Nothing radical. Its like "inletting" a pre-carved stock.
Dry firing and evaluating my grip ,natural point of aim,etc...I made a discovery with the Shield. The textbook "align the gun with the forearm" and "place the pad of the trigger finger on the trigger" .....Yeah.its OK.
But I was working on quick ,consistent sight acquisition and not moving the gun with trigger pull. I do have a couple of "landmarks" like "This thumb contacts here" Trigger finger parks here" but I found the most consistent "good results" came with my "panic grab" grip. The trigger finger(when placed) was in the first joint wrinkle . This was with the little Shield and my hand . I don't do Weaver and I don't scrunch my neck . My arm is offset from my eye. Facing the target,I bring the slide up to alignment to my eye. Guess what? The gun cannot be in alignment with my forearm.Its about 15 degrees off. I quit worrying about it.
There is a natural , anatomically correct, balanced skeletal stack that your body knows. Its in your operating system.
Simplify your "list" to the draw and bringing the gun up to alignment with your eye. Yes,maintain safe trigger discipline and find your sights.
Your focus,IMO, needs to be on situation. Shoot? Don't Shoot? Run? etc,
Get the gun from the holster to your hand. Bring it to alignment with your eye. Process whether to Shoot/Don/t shoot. Move to someplace better.
Certainly you need marksmanship competency. Work on that . Its a good thing.
Four inch groups or eight inch groups may be academic at conflict distance.