Add to Cart label by Attribute / Custom Taxonomy

Hi,
Thank you for this great plugin.
It would be great to see it possible to define a custom add to cart text based on product’s attribute or taxonomy. This way I could control it by availability and show “Pre-Order” if the product belongs to the “Future Release” of the “Availability” custom taxonomy, for example.

As a side note, would also be helpful to define a different label for in-stock and backorder products.

Best regards