There used to be a vaapi build of mplayer but it doesn't seem to be maintained any more and doesn't work in Vivid.
Default mplayer2 build from the repo uses 40% of CPU during 720p playback. Same as totem. VLC does have some hardware acceleration support and uses 13% but I liked mplayer's UI more and it used less than 5% with.
Is it currently possible to use mplayer with hardware acceleration on Intel integrated graphics?