Hi @dagwit00001
I don’t think the game can tell you how big the download’s going to be on the “Checking for Updates” screen, as (AFAIK) it is while on that screen that it is determining what is installed on your system, and therefore what needs to be updated. Once that is done, the subsequent screens provide the required disk space, etc.
I agree that because the “Checking for Updates” screen can be displayed for quite some time, letting us know what is going on in the background would be useful. Many think that the game has hung when the screen has not progressed for a while.
There is a wishlist item similar to your idea:
But you might consider creating a new one specifically for when updates are applied.