"Excellent luck" is an interesting twist. I think I'm going to use a variation on the Fudge/Fate Ladder for number. In this system, instead of Hit Points, you have Luck, which starts randomly every session at 6, 8, 10, or 12 by pulling a random die out of a bag of d6s, d8s, d10s, and d12s. (As you level up, d6s are removed from the bag, then d8s.)
I'm concerned about the extra cognitive load of remembering that "excellent" means "10," but I think it's worth it for the naturally memorable words.