I tried CO2, still have the bits in a box somewhere.

Have used a Topeak Road Morph for years... the gauge is broken however.
I like a hose on the pump for some reason.

The last flat was a new drywall screw through both sides of the rear tire, it was hitting the V-brake arm pretty good. Clack, clack, clack.
I average about one flat a year. Generally the rear. The front kicks up the bit and the heavier weighted rear picks up the bit.

Even though I'm running 700 tires, I still carry a good used patched 26" tube to assist those in real need.

I powdered car tubes/tires in the early '60s, did the same with tubed m/c tires and still powder bicycle tubes at install. Tubes run cooler and do not stick to the tire or rim.

In my experience, Schwalbe tubes hold air very well, in 26/2 @ 50psi i only needed to add air once every three weeks. YMMV.

Many years ago an old roadie that was a member of the LA Wheelman told me of installing a bit of stiff wire(like a piece of spoke) bent to the contour of the tire, set to just rub a bit.
He swore that this would flick an offender out of the tire before it could work its way into the tube.