It would be nice if when uploading images, we could set the default 9-slice of that image, so that when we use it in GUI, we don’t have to open up the image file, and re-get the positions of everything.
Also, having it editable later on would be lovely, because some programs measure pixels weirdly, and it may need to be adjusted later on.
I think Gimp measures the mouse cursor pixels based on the centre of the pixels, whereas paint.net measures it based on the whole pixel. I’d have to double check, but I just remember being messed up before due to something like that.