We do category cards too but sometimes life is too busy and we forget a month. For everything else, the Citi Double Cashback card is king at 2%. Fidelity has a similar 2% card too which encourages saving.
There's other benefits too such as rental insurance, price matching, and extended warranty. I've had to use these before and it was super easy as long as the paperwork is followed.
Virtual credit card numbers are also awesome for signing up to subscription services that are difficult to cancel.
My favorite was the Chase Sapphire card we had a few years ago. The sign up bonus paid for a plane ride across the world, entry into airport lounges (awesome for long layovers) and free meal/drink credits at the lounge bars. It cost a fee after the first year so we dropped it.