Yeah, I initially turned off animations on my phone maybe a year ago or so. Works great unless you occasionally play games (QuizUp for example!). Then animations needs to be able to show something, otherwise the game UI is laggy. Setting the animation scale to 0.5x fixed the issue, and still my UI feels very snappy.
If you turn one of the three animation settings to 0 on a Keyone phone, the popup to choose charge/fast charge/data connection when connecting to USB doesn't appear and there's no alternative way to select it.
I forget which but stuck with 0.5x for that reason.
However, I've notice Android occasionally uses animation to convey things to the user, so I'll try your idea of halving it.