Every bike is a balance. And depending on your set of components and wheels, that factors into it noticeably. Obviously most importantly is the color scheme of your Prologue. I forget if you have the red/white or the grey/black. As I was able to obtain (having wanted it in the first place) a grey/black version, I wanted the components to be dark on it. And more speeds than just seven. Almost immediately the quest for full 7900-era Dura-Ace began. Between that and arriving at the optimal stem/bar combo, she is, pictured below, in her best form. And just a touch over 19 lbs (19 on the money or just under without bottle cage) with pedals. I'd love a set of deep section carbon wheels as that would look even more sinister. As it stands, you'll notice these WH-7850 (7800-era Dura-Ace alu/carbon medleys) are pretty low section by modern wheel standards. No traditional box section MA2/MA40s (which I very much like), but squared off in section no less (no V-shape at all). The wheelset's light weight (1431g) and lithe aesthetic truly complement the frame's light weight and lithe nature. The black and grey of the groupset matches the paint, and works to make this smoked and sinister looking bike.
Red/white Prologues (or any red/white bike) are tough to visually compose. It's either fully or near fully traditional (silver components, 7-speed, silver rims or MA40 dark grey) or fully aggressive with all black components and deep section wheels. The red/white just sort of sits on the fence, visually, to me, and it's up to me to take it one direction or the other. It offers no hints or desires, unlike, say a black or dark colored bike.
Anyway, here's what I have, and I think it's one of the best ways to compose this bike (there are not many bad ways to compose a grey/black Prologue, IMO).
[pardon the interior shot]