The internals are fine as is. I would forego the 3-hole match trigger and get a simple trigger but get a good trigger job (unless you plan on competing). I am not a big fan of 'extended' this-and-that as this stuff can get caught on clothes, etc., but if you have small hands or like it, then go for it. I would ship the slide off for new sights. Otherwise I think you are good to go.
Regarding the 1911: "The gun was designed to function. If it's built to the proper specs...it'll run. It's a machine. It doesn't have a choice." 1911Tuner