This attribute always felt unimportant. In Daggerfall spells always worked a little better and random loot was also a little better with 100% luck but it was almost unnoticeable. Don't remember ever using it in the other games.
To make a luck attribute more interesting i would suggest adding negative perks when luck is too low and positive perks when it is high.
If these perks are fun to play and add interesting features to the player character I could see players having low luck just to play an unlucky character and experience funny reactions from npcs or just for the challenge.