Complex Product Variants

I have a product (a modular bed frame) that has a lot of options (size, wood, height, leg style, finish, etc.) which makes for a product that has hundreds of potential variants.

It seems that Squarespace is quite limited in the way it handles inputing product variants/options.  As in each and every possibility must be input manually and separately.

Is there a plugin that helps with that?  Or some technique that I am overlooking?

Other platforms have much more highly developed variant engines. 

Is this functionality something that could be added to a squarespace back end by a developer?

Squarespace variants work in the way you have described. There's no backend access on Squarespace, which means that developers cannot add functionality to improve features like this.