The Propel forgoes paint to keep the weight down, but I believe that the weight still includes ISP, carbon dropouts, BB insert etc… I guess paint could be viewed as structural.
As already mentioned above, all the high end bikes ride very well and just present different flavours of something very tasty. The OP has started with a fine bike and wants something that “feels” superfast. I’d start by adjusting the position.
My Giant Defy (Medium) came stock with a 100mm stem on a 54cm top tube. When flipped up with spacers, it would be a very relaxed position. I’m 5’10” and normal proportions, so switched to a 125mm flipped down stem, and with 0.5 cm of spacers, this mimics my racy (not really) TCR position. So, as I said before, adjust position first then if that isn’t doing it on the “superfast” front, think about something with even more aggressive geometry.
I think it is ultimately a question of fit, not frame.