There's a lot of ground for discussion with regards to will power, wisdom, spells and saves.
For example, Charisma is said to represent force of personality. So there's an argument for Charisma representing willpower.
Wisdom is said to be in tune with one's surroundings, while Intelligence is analyzing information. But don't you need to analyze the information of your surroundings to be in tune with them? So maybe Intelligence and Wisdom could be merged at the cost of some resolution.
Some claim Wisdom also represents accumulated experience, while intelligence represents book learning. Yet there is a literal experience measurement that has nothing to do with Wisdom. Perhaps Wisdom better represents the senses, but does this mean someone is wise simply for having a keen sense of smell? Would a renowned philosopher be considered a fool when he gets older and buys a hearing aid?
In BECMI, only Wisdom gave bonus to saving throws against spells. And it was all spells.
So you see, this is all a ploy by Cleric players. They want WoTC to dump Wisdom as an ability, change the Cleric's primary stat to Charisma, add Charisma bonus to Will saves so the Clerics can slay all the Bards. Now it is time for the Cleric to seduce the barmaids. All of them.