i think a daily skate session is a great way to move slowly, but 3-5 hours a week of just skating around a rink sounds a little dull. but, if it's fun for you, do it. personally, i'd rather strap on some rollerblades and go somewhere.
and hockey should serve as sprinting. the intervals of intensity and rest make for a great metabolic workout. you may also want to think about running some regular sprints too though...i imagine that will only help to improve your skating.