So, Wish?

Mom, can I have Fix This? No, we have Fix this at home.

Fix this at home: Fix boat

Points at BBEG : Fix this.
BBEG's mom walks in.

A wizard archetype that lets you sacrifice known spells for more slots would be sweet

Points at army: “Fix this!”
Army regresses into infant-hood and is rendered incapable of battle.

Points at own army: “Fix this!”
Army is buffed.

How many times is this just a neuter/spay magic?

This is actually a thing in JoJo's Bizarre Adventure (Crazy Diamond). It's fun to see how they can make up cool scenarios with it:

Feats of this nature include trapping an enemy by restoring pieces of a broken crate around him; exposing a Stand formerly bound to an object; and tracking by restoring a severed hand, forcing it to seek out and reattach itself to the body from which it was cut off.

https://jojowiki.com/Crazy_Diamond

I just realised that this is basically the plot of Redo Of Healer.

I’ve had a concept I’ve wanted to try for a little while for a special type of wild mage, but I’m not 100% sure how to implement it. Instead of wild magic just being a completely random chart of spell effects with no control over what you get, the spell caster would declare what he wants to end result to be… and the DM, or some more limited random mechanism, would choose what spell (of the appropriate spell slot level) might get them closer to that result. If they want to get past an ogre guarding a treasure, they might cast a fireball, or maybe invisibility, or maybe some sort of teleport effect… they all advance towards the stated goal, but without the caster’s control of how, leading to the wild magic feel without the insanity and campaign crushing randomness other wild magic can bring. And there’s still room for some silly danger, as maybe the fighter is next to the ogre when the wild magic chooses fireball.

This is a little like Mashle except instead of a spell the main character just uses fist to fix every problem

Childhood trauma of npc or other player? Fix this!

Sound more like a cleric kind of thing.