Overpowered Enchanted Tools as Treasure Enchantments

I think this is a good idea that encourages exploring the world and end cities. So hear me out:
I think we already know in order to get Diamond Pickaxe with Efficiency V requires at least two diamond pickaxes with Efficiency IV and a anvil and some XP. But what if you could find Enchant Level that is higher  but not possible via Anvil unless having a book of it? Like we already have Frost Walker, Mending, Curse of Binding and Curse of Vanishing, but if we make almost every single tool have an additional level that goes beyond limit? It would be totally amazing! Imagine having a Diamond Pickaxe with Fortune IV? or a helmet with Respiration IV? In my opinion I think this would make Treasure Enchantments more than a solid reason to find them. And perhaps maybe as a bonus, tools that have treasure enchantments could have a golden aura instead of purple.

So what do you think about this? Do you think this is a great idea or is it a bit too overpowered? Maybe something more would require for this to work, perhaps?