Everything:
Tube
Lever
Hex key
Patches
Fiver
Pump
Co2/valve
All goes in a small case that lives on the worktop in my man cave next to my helmet, Garmin, gloves, glasses, gillet and lights. I don’t find it difficult to to select what’s needed before I set of out and put it back when I return. The bike is easier to clean and maintain without stuff strapped to it and things don’t need swapping between bikes.
You can carry stuff however you like btw it doesn’t bother me, I’m sure you feel the same about my arrangements which have been fine tuned over 30 years and work very well for me.