You can get a 3.5lb connector and that helps, also an over travel / trigger stop. This will make a big difference, then you can take it further with swapping out springs with a wolf competition kit. My trigger reset became slow and mushy after replacing the trigger spring, I think I'm going to put the factory trigger spring back in, but leave the wolf striker spring and firing pin block spring in place. You could also swap out the whole trigger group with replacement like Vogel, Travis Hayley skimmer etc.. but I have no experience with these.
In my opinion night sights are a waste of money (mostly). Glock sights work, Snake eye's from Dead Ringiner are different... and what I'm using now and like are the Trijicon HD night sights with the rears blacked out. This combination has worked well in IPSC / USPSA and tactical classes I've shot in.