There are times when it is useful to put all of "something that you have a whole mess of" all to the same place. Then, there are times when it is not.

Is there some way to change how the new Quick Stock works, or are we stuck doing them one-by-one if we have a detailed idea of where things should go?

Hmm, I'm not quite sure what your asking but I will try and help explain.

By the looks of it items you have multiples off group together in the quick stock list for easy moving.

However, if you look to the very left side of the table there is a small box with a + in it right before the item name. If you click on that box it will open up that group of items individually, so if you'd like to put only one in your shop, simply click on the expand + and then click on the individual item to move it as you'd like?

Aha! Yes there is a small box for that, silly me. Thank you for your help!