Hm....
>>Trigger pull
ammo choice
brand of ammo
use of a highcap magazine
use of skateboard tape/grip modifications
choice of caliber
number of safeties
hammer down: good / hammer cocked: bad<<
Just IMHO plus what I've heard over the 37 years I've been involved in LE and carrying....
Ammo choice, brand, and caliber _should_ be something like what the local PD is carrying. Juries don't really understand any of this anyway, but if you can show that your ammunition choice is less than or equal to what the local PD is using, that should cover you. Wadcutters or SWC should come across as "target" ammo, and "more accurate", an attempt to be very careful of what you hit, and to limit penetration to avoid hitting the wrong target. DO NOT use "Super Felon Blaster III" or something like that.
I don't see anything wrong with carrying a .40 or .45 if the local PD is using 9mm's, particularly the .45, but you may need to show that the choice was made because it's a better way to _stop_ an assailant. Jurors may not understand any of this except which one is bigger, though. Just make sure your lawyer does....
Number of safeties is probably irrelevant as long as what you've got is what the manufacturer supplied. IOW, don't remove the magazine disconnector, grip safety, etc.
HiCap mags are also irrelevant if the manufacturer provides them with the weapon. Aftermarket mags might be a problem in this sense.
Grip modifications should be approached as "to improve safe handling", and should be OK as long as it doesn't look like a zip gun. Commercial aftermarket grips, in particular, should be OK. IANAL, and all that, but this is kind of neutral as long as it doesn't diminish safety.
IMHO, the hammer down/cocked issue is a grey one. SA's are just a lump of metal (& plastic) when not cocked, but a shark could accuse you of "looking for trouble" anyway. Establishing that the only way the weapon is useful is when cocked may be tricky, but I know a lawyer who could do it. DA0's and DA/SA, if fired double action, shouldn't be a problem.
(Not that the lawyer's couldn't screw you over because of holster wear....)
The key to trigger pull changes has to be _safety_. "This improves my control of the weapon", rather than any sort of "makes it easier to shoot somebody." Your lawyer should be good enough to deal with this. Just smoothing the thing out shouldn't bother anything. Trigger pull should be left approximately where the factory set it, or at least not reduced below whatever the factory calls it's minimum for that gun.
(I've got a Commander that's something like 15#. The former owner was a diabetic and had neuropathy issues. He _had_ to know what the trigger was doing, and for him, that heavy trigger resulted in safe control. When I get a chance, it'll get put back to stock. While you could now call it "difficult to discharge", I have control issues with it and a shark could make something out of that. Taking it back to stock (8#?) shouldn't be an issue.)
The problem here is that in the absence of protection from civil liability, _anything_ can be used against you, including running away should the bad guy damage somebody else.... It is, however, and IMHO, best to keep the obvious red flags down.