I certainly could add such a thing here. The big concern that I have is that it increases the complexity of what is currently a very simple system. Right now, you just have a button, "Upload an image" and when you click it it does just that. You select one image and up it goes. Then click the button to add another one.
There is no way to make that dialog box permit you to select multiple images. So, in order to get that functionality, an entire widget has to be created that lets you select them one at a time and then when you are done, you click an "upload them all" type of button. That's a lot of "stuff" to add to that area of the page.
I agree that uploading multiple images at once would be really convenient, I'm not sure that the extra complexity would be worth it.
