So we all have skills and magic in a game that begin to lose its shine, such as a Firaga spell would be used in favor of a Fire spell because of higher damage output, a Curaga spell over a cure spell, an instant-death spell that doesn't see much use in many battles, or a character has too many skills that seem overwhelming and you'd either go for the higher combo attack or the higher damage output ones.
How would you combat this?
As for me, in my game, I intend to make even the first skills learned, just as useful as the ones learned last:
A simple fireball attack can damage the enemy, but why stop there when you can add status effects to it as well, such as add a Burning state to the attack?
A wind healing spell, Aromatherapy, can recover HP but with some small side effects, such as adding an ailment like sleep.
Or healing spells that add some sort of buff, or a buff that increases ATK but decreases DEF.
A melee attack that not only just deals damage but can knockback, stun an enemy etc.
I got the idea from playing the Atelier Series games where each skill not only deals damage or heals but their usefulness with status effects, or changing the course of battle, is what makes you want to use them more often. Even though the games did not have many skills to learn, the skills themselves proved useful in battle, providing more strategy.