You're not going to affect weight much unless you do something more drastic, like taking the quiver off(my choice). Also, shooting without a sight, will drop a noticable amount of weight. Lighter setups are more easily acheived by avoiding parallel limb bows - long risers are simply heavy. You can save anywhere from 1/2 to a full pound by switching back to a traditional style riser/limb configuration. They have more recoil, but shoot just as accurately as any other bow.

I'm one who has never enjoyed hunting with a heavy setup. This year I'll be spending some time in the field with a longbow and hip quiver. It weights something less than a pound.