The BFG ball - what an odd asset to focus on.
I wonder if you've looked at some of the others? The BFG is more of the exception than the rule.
I suggest you take a look at this:
https://doomwiki.org/wiki/Aspect_ratio
I very much disagree with Hellser about why GZDoom does 1:1.2. It isn't because we'd get reports about it not looking like PrBoom or other source ports - it is because it is the correct way to render Doom. Doom was designed for a canvas where each pixel was stretched 1:1.2. Even if not every asset doesn't fit this perfectly (the BFG and Doom Imp projectiles are good examples of this), many more assets were.
For example: The status bar mug shot was very clearly designed with the stretched aspect ratio in mind. The Soul/Mega/Invulnerability spheres will look out of place if they get squashed, too.
Remember first and foremost: This is a source port for a very old DOS game. And while there are many features that allow it to be used as a game engine for more modern games, it still has its roots in that very game - and that is something that it cannot cut away from, without losing its actual purpose.
That being said though, HUD sprite scaling is something that, in my opinion, should be there as a modder option similar to PixelRatio, and therefore, as Hellser said - should be suggested.