The only attack worth "not" learning to increase the chances of Wishing Star is Angelo Strike. Recover, Reverse and Search all occur randomly during the battle and won't appear upon using the limit break (Rush also works like this, but is learned from the start). That leaves Wishing Star and Invincible Moon, both of which are highly useful and desirable during a battle. As for the chances of each coming up I imagine it is probably more related to your "crisis level" rather than your luck stat, much in the same way the game decides whether or not to use Lionheart.