Other than sights, for EDC, I’d say there’s a contingent of those who will say leave it as is. There’s the liability consideration … do you want some lawyer to say you have a “dangerously light hair trigger” … as well as keeping what’s known to work as is, left as is. A lot of modifications are done by competitors for legit reasons, but for carry, sticking with oem isn’t a bad way to go.
There’s lotsa’ threads on sights, which are a personal thing. For me, the stock “drop in a bucket” sights work quickly and accurately enough, though having night sights is a good idea. That said, in a gunfight, sights aren’t really used. I practice fast, rapid shot strings of 3 rounds at a time with tape over my sights … my goal are 3 hits in an 8.5 x 11 target at 7 yards as fast as I can.
Lotsa’ threads on holsters, but how much do people practice their draw from it? Do it hundreds of times, and going backwards, from the ground etc and you’ll be a lot more prepared than burning up thousands of rounds at the range in static fire worried about tight groups that look pretty.
Sorry, if this is a buzzkill, but you have one heck of a SD gun and the best “modification” for it is practicing with it!