I like thinking about equipment. I don't necessarily buy stuff but I think about it. I know it's a low % of the overall equation but it's still fun. Tall wheels which are reasonably aero are one of the more significant things you can get to immediately affect your top end. It's faster at 30 mph, 40 mph, especially with a cross tailwind. They transfer from bike to bike quickly and they generally last a long time. It won't allow me to time trial like a Cat 1 but it may help me stay on their wheel for a minute or three.

I don't think much about lower return stuff like cranks or hubs.

After extrapolating the significance of a flat aero profile top of the bar I'll think about that a bit, ditto a super skinny aero seat post. My bike is so short that aero or no aero doesn't make much difference in most of that stuff.