Hobs, it's because you played the original Metroid too much. If you haven't finished with 100% on Hard mode, you're not finished. It's a handheld game; it's not supposed to be long. The Metroid games are about quality, not quantity. Super Metroid can be beaten in a half hour and no one complains. You probably played it on a ROM, so you had a bigger screen and savestates.

</fanboy>