Hi,
The variants are indeed no adapted to have a lot of variants for one product.
But for some variants, it is perfect. The variants don't handle only the price, there is a lot of other informations that can be personalized per variants, the name, code, quantity, images, files, custom fields...
In your case, if only the price change from one variant to another one, yes it is indeed not adapted.
It would be better to use, for example, a category for the main product name, and then products for each variants.
Then to populate the price, you can potentially use the mass actions. Else a custom plugin based on custom fields could be the best option.