[TorqueDog]

I've recalibrated my tipping behaviour; this 20% base tip on the machines with amounts going up to fu-cking 30% of the post-tax amount is insanity.

If you sucked, 12%. (You won't lose money after house tip-out.)
Met expectations = 15%.
Met expectations at a higher-end establishment (those expectations are higher, after all) = 18%.
You remembered me and/or someone in my party and greeted us accordingly, server welcomed me by name after being seated (if I made a reso), provided a friendly environment and great dining experience = 20%.

Tipping more than 20% is not happening unless I heard through the grapevine that your cat or dog needs surgery and there's a GoFundMe.

Also, don't tip on tax. If the machine offers a custom % tip, roll down 1% from the intended tip percentage to get roughly the correct amount.

For places where the service is "handing me the thing and popping the amount into a register", I don't tip. Fast food, coffee places (unless it's the type where they serve you at the table -- rare), nope. The owner is pocketing that sh-t.