So let’s say we are selling T-Shirts.
We create the T-shirt as a product with a variant on the size.
We setup multi quantity.
The customer then selects 2 quantities and choose size small.
But what if they want 3 medium too?
Could be cool if they could click a + sign or whatever, and duplicate the product so they can choose both 2 small and 3 medium.
Right now we have to create products for all sizes if we want the user to be able to select multiple sizes - right?
That’s what we love to hear @SubZero !
An idea that’s crazy enough but still useful hhh LOL!
That’s kind of nice idea to be honest… so to put it on other words need the ability to pick multiple quantities of not just products, but also variants!
That’s good, I personally find it useful 
it will be challenging to put together at this time as Multi-Qty is still on it’s period hhhhh, So it’s a bit moody right now 
it might break or do some crazy unexpected thing anytime… we will make sure it feels better and more integrated and bug free… before complicating it further
For the time being what I suggest to do is this:
Create your t-shirt products on size… meaning do not use Size as a variant but rather as the product itself…
That will help a lot, and will allow you a room to increase price as size goes up (which is the logical thing to do).
Colors, Styles…etc then can be variants… thus your customers will be able to pick different sizes, being charged differently (you can keep it as same price though)… but eventually they’ll get charged differently.
Another thing to keep in mind, is Credit Card e.g Stripe, if we are going to complicate it further it should be able to work for all scenarios for both Credit Card and PayPal, and the setup above should work just fine.