Any question answered...

A power meter will help you train to wattage, which, some say is the best way to train.

Those some people also say that improved fitness gives a greater advantage than weight or aero gains, broadly speaking.

This is what I was thinking. Fitter and stronger is better under all circumstances. While wheels only help in some.

Get the wheels; are you still at GPS store?
I thought this too, need bling. And no, St Paul's now. On Ludgate circus.