HEVC 10 bit in order to reduce banding for animation, especially during dark scenes. I know H264 Hi10 exists, but it has poor hardware support, so using HEVC 10 bit is the best option (I don't own a single streaming device that supports HW accelerated Hi10, besides my PC). Also, an added benefit is reduced file size. I find that doing my own encodes is very rarely worth it, but when I do, I use FFmpeg in the CLI and not tdarr.