I think @one1 is 100% correct, the giant quotes images annoy me too; the use case of the quote is to refer to it, not show it again.
While this is true:
I believe that might be the lesser used form.
So I would optimise for what I believe is the most regular usecase: quoting in the same topic.
Scale the quoted image down to our smallest size
There is always the arrow button to easily go view it in its original context and size:
Or you can just click on the “thumbnail” image and see the full size again in the lightbox.
