Greasy Fork is available in English.
Moves the controls under the video and makes the UI look like it was before august 2015
I've added an extra option to hopefully satisfy your request (and the request from q1k for transparent controls).
The new option is to revert the colors to their original light-gray on dark-gray (default=true). If you turn it off, it will look like the 'new' controls but they will never hide and will be under the video to not obstruct anything (the bottom-gradient will also be turned off).
Some Suggestions
Can you just leave the new YT player look and only disable auto hide pls