ebisu is an elite teacher....he trains hokage candidates.....so he cant be THAT bad (although then again i dont think he trained anyone who has yet BECOME a hokage [img]i/expressions/face-icon-small-wink.gif[/img])
but he knows his stuff......and naruto needs to learn the basics, which you cant deny

but most importantly, kakashi couldnt train naruto since he had to worry about sasuke