New wheels, carbon fiber frame, and the latest and greatest drive train will buy you close to zero more speed. It would gain some proportional to the fraction of weight saved and grade of incline, on the steeper hills (maybe a tenth or two mph overall). Some people put a lot of stock in "stiffer" giving better "power transfer" and while we lose some power with a noodly feeling bike, it's usually overblown IMO. Not counting flexing the brakes to the rim, it surely isn't more than a fraction of a percent of power lost in flex, which comes to even less of a fraction of speed.
Racing tires & tubes, aero equipment and freer bearings is where the speed gains are. Body position. How much depends on how you're riding that Trek.