I was under the impression the DAO has a 7.5lb trigger pull where the stock SA/DA has a 12lb Double action pull. It should already be lighter, right?Looks great! I did the name on a P220 a couple years ago...
Now that you've done the SRT... Take a look at these goodies from Armory Craft...
https://www.armorycraft.com/product-page/p-series-Trigger-Pull-Reduction-Kit
along with the dual adjustable flat trigger...
https://www.armorycraft.com/product-page/sig-p220-p226-p227-p228-p229-adjustable-flat-trigger
With the SRT, the reduced pull kit and trigger will make your 228 a sweet(er) shooter.