While I definitely don't want to see this become standard, I don't think it will be nearly as broken as people think, even in Little Cup. In Little Cup, even if a Potion can completely heal your Pokemon every two turns, that's only the same amount of health that two recovers would give you. So spamming Potions would be exactly the same as spamming Recover+1 attack every two turns.
In Lv. 100, it takes a lot more turns to get a Full Restore, so you can't spam them nearly as easily. The boosts can be easily countered by Phazing, Hazing, or simply hitting the Pokemon hard when they use the boosts. Cradilly is pretty bulky, but it's still slow so you have a chance to 2HKO it before it can get both +6 Spe and +6 Atk. Mountain Storm and Ice Breath can also completely ignore Defensive boosts because they always land a critical hit. There's also Scarf Ditto to take into account.
Due to the number of this that have already been overhyped, we definitely need to test this before we can say it's completely broken, and I doubt it will become standard regardless of what we find.