I have kickstands on all of my touring and city bikes. For me, they're incredibly valuable and I use them all the time.

If there's enough room and the stays are beefy enough at the regular kickstand area, I clamp them there with a bit of old inner tube or cloth bar tape wrapped around the stays to help protect them from scratching/spinning.

I've used rear-mount stabilizer style kickstands on bikes where they're necessary (old MTBs with u-brakes, converted for city use).

I usually just use regular greenfield style kickstands with the greenfield rubber boots that slip snugly onto the end. I bought a bunch of the boots in bulk when I was doing a Niagara cycle order a while ago since they were only like $0.75 per boot. They help give the kickstand a little more foot coverage and help prevent it from sinking into dirt etc.

I don't put kickstands on lighter, faster, racing bikes, but I don't end up riding those as much either.