The wheel thing: Probably not. Wheel upgrades go for aerodynamics and weight, really. Bear in mind that I have no clue what I'm talking about.
The frame thing: I've found that relaxed geometry aluminum frames are awful, but the aggressive ones are fine. Perhaps not carbon-comfortable, but then I haven't had the opportunity to test much in the way of carbon frames (that actually fit me, anyway).It's really hard to tell because everyone labels their specific carbon or Al tubing differently. Granted, geometry plays a role in how the tubing goes together and how it transmits vibration, but: Take a look at the same company's road bikes (not the endurance frames), and then if they have a "crit"-oriented road frame, take a look at that too, and compare. While I never had to deal with tri/TT bikes, I'm willing to bet that the carbon used in a TT bike is all about stiff and light, so it may be a wash.
No way to try one, huh?