What is the new feature or improvement?

Adding the possibility to have a cooldown between uses for a better balancing. I remember playing with ProjectMO on forge and loved the veinminer because of that limitation. It didn't feel overpowered unlike any other veinminer mods. Even with limited distance, the fact that you can just use whenever you feel like it makes it op. on Project MMO there was about 2 uses per day a bit more when you leveled up if i remmeber correctly. It would be great to have a similar limitation like having a cooldown depending on the enchant level.

Were there any indications of the cooldown time? If I added this, ideally I'd like to include a good way of informing the user that the enchantment is on cooldown and the remaining time left.

I think it's even better than a timer as it still gives you some usability even when you have few charges.

I didn't remember well but i checked on curseforge and you can see a value raising on the bottom left

the vein ability charge up to a maximum depending on your level and you could use it to mine whenever you wanted if you have charges. The only thing is that vein mining 2 blocks isn't usefull so i always used it when it was almost full. That's why i remembered it as if it had a timer.