On the subject of wheels, tire choice is pretty important. I run tubed tires instead of tubeless or tubular because they are just easier to deal with.
For time trial, there are a couple of things you are looking for, rolling resistance and aerodynamics. Typically these days, wheel manufacturers are designing for a specific tire to maximize aero. This way they can make sure that the tire isn’t wider than the wheel and nothing is poking out and hitting the wind.
Conti 4000 s2 have been a popular tire for a while. 700x23 is recommended for the Flo fleet of wheels (and I recently learned for Envy as well.)
I have also run supersonics (no puncture protection) for reduced rolling resistance, but I don’t want to ride them around daily or for longer than a 25k TT.
Speaking of which, don’t run gatorskins! They have such a huge penalty to rolling resistance that you could change 3 flat tires in an iron man and still be faster!