It seems like a lack of resampling after using the move tool is a critical feature to be missing? After upscaling images, the result is very pixelated and should be resampled. Leaving that step to the end when exporting doesn't give a very good impression of what the image will look like while working on it.
I considered the method of putting a layer into another document and resizing there, but that leads to horrible workflow + doesn't give reference to what size it should be, in relation to other objects.