I don't mess with "perfection"..... aka..... the 3913/14/NL
If you're going to mix and match 3rd Gen parts.....might I suggest you build yourself a 6915....... my answer to the 80s Colt CCO.
6906 frame mated to a 915 barrel and slide..... Gives you that longer sight radius you want and is 12+1. IMHO , after 30 years of doing it, the butt of a 6906 is no harder to conceal than the 3913's. I've got two. One I built and one I got from Squidsix. One with front night sight and the other with fiber optic front sight.
I noticed that some of you are now using the Hogue rubber grips..... FWIW I find the Hogue checkered wood grips don't grab on the cover garment as much and don't add any bulk. And while we carry concealed the wood adds a real touch of class;especially to the 3913NLs and 3914s!!