My opinion is that hiding as it is should be removed from the game. Hiding should consist of a sneaking skill, where it allows silent walking, the higher the lvl, the more silent and for longer you can do it, as described 2 posts up, and camo gear. Camo gear should be all that is needed beyond sneaking to make yourself hidden. This puts the ability to hide into the players ability as well, rather than just render the character invisible.

Im certainly not a fan of the invisibility ability.