I prefer to use #SMPlayer as the video player on #Ubuntu, despite the CJK characters in title bar can't display correctly from time to time due to the text encoding. However, there aren't any better alternative.
As for #MPlayer, which is the core of SMPlayer, is so awesome that can run at terminal but it's too complicated to configure. The manual is too long for reading.
@dqwyy Try changing SMPlayer's backend to mpv, and enabling interpolation. That combination is the best I have ever experienced in a media player.
We are a cute and loving international community Ｏ(≧▽≦)Ｏ !