Suspend, most of the time. I have a two handed Vulcan nerve pinch keybind that does that for the end of the day. A desktop PC doesn't have a lid, but that keybind is about as cathartic as closing a laptop.
This is actually different from how I have the desktop environment set to do it, which is the hybrid suspend/hibernate option. This gives me at least a couple of options without too much messing around. Quick shutdown: Use keyboard; Hybrid: Use GUI (which can be done by keyboard navigation too if absolutely necessary.)
The reason? There's a surprising amount of state, such as open windows, browsers, etc. that need to be set back up if coming back cold from a full power off and that bothers me more than maybe it should.
By rights, I should use the hybrid option all the time as it's technically safer, but it takes longer to power off and it actually suspends then unsuspends for a few seconds as it sets up the hibernation profile, which gives me the willies.
Also, the power grid is pretty stable here. If I was elsewhere I might be using the hybrid a lot more.