Well, I hate to tell you this, but there just isn't much to do. Leave the main springs ALONE. They are about as light as practical to insure reliability as they come out of the box.
I do not understand moving the hammers closer to the firing pins?? You'd want to do that why?? How?? The only modification to the hammers I have ever done is/was to remove the stylish little horns on the top of the hammers. The're swell little meat slicers.
A nice cushey recoil pad would be nice.
Switch Triggers is cool for the really fast guys.
Breaking the sharp edges on the chambers is a good idea. Funneling, not so much.
I may not have helped much, but honestly, beyond a little rubbin and buffin of the mating/contact surfaces, there just isn't much to do.
Coffinmaker