OP, you ruled out my advice - a good, full size frame pump. 100 strokes to full pressure. The ability to off tires. The freedom to drop tire pressure for a portion of the ride (gravel, say) and easily pump back up for the 35 miles home. No - how many flats can I repair? I've had several rides over my years of riding that just happened to be bad days and I've had to pump tires from scratch a half dozen times or more. (And rides with others where CO2s ran out and mini-pumped arms failed.
In fact, good frame pumps work so well no other inflation device is needed (unless you ride tubeless for the bead seal as mentioned above). In my racing days, I owned two pumps. A Zephal HP on each bike. I rode sewups. Race wheels were silk/latex and got pumped from scratch every race.
Now, modern bikes make carrying the best tool for that very basic necessity of tire inflation impractical. Yes, I know. Frame pumps are heavy, so non-aero, klutzy, old-fashioned and dumb (and in a pinch, surely some old fart will have one so I don't have to). (Rant, rant
)
Ben - who's may have crossed frame pumps on his tombstone