I typically agree, and rarely even bother to look at the Special Features.  I don't usually care about deleted scenes.  Sometimes--upon other's recommendations--the gag reel/outtakes are funny.
I do like some commentaries.  The ones on the Criterion collection (Rashomon, for example) are usually very good, often scholarly, and for some films, that's appropriate, and interesting--to me.
A few directors are almost always interesting, again, to me.  Like Soderbergh and Robert Rodriguez (Traffic/Limey and Desperado, respectively).  John Waters is always funny and gave my all time favorite commentary for Pecker.