Ok, so I know this may seem like a small issue, but I believe you shouldn't be able to fire while on Debris.
My main reasoning for this is because many lists are able to take advantage of debris far beyond what any list is capable to do similarly with asteroids (even swarms, which gain a slight edge by bringing smaller asteroids, hardly gain as much leverage). Here are a few pilots that can gain a large advantage over their opponent simply by bringing debris over asteroids.
a) Dash. He effectively ignores debris fields, as they have no effect on him whatsoever. Asteroids, due to the firing restriction, at least forces him to barrel roll off of them so he can shoot.
b) Yorr. Since ships can fire while on debris, and Yorr can redirect stress to himself, ships within range for his ability can effectively act as if the debris is not there for the small price of stressing a shuttle which is only mildly inconvenienced by it.
c) Dengaroo. The amount of map control this list has because Dengar doesn't care about stress is insane. With the white 2 sloop and green/white hard 1, he can sit around and on his debris for nearly the entirety of the game while the opponents ships struggle to weave around it.
d) Hera crew VCX. They are able to do their reds at any time, and with FCS, they don't need actions anyways, so the stress stack is no problem. In fact, if they have Ezra on board as well, it's even beneficial.
e) Stresshog. He's going to be stressed anyways, so debris is not a big deal at all.
If you haven't noticed, each of these are components of what many would consider (or used to) as "top tier" lists, largely because they don't worry about stress.
tl;dr
Due to upgrades, pilots, and synergies coming about in the game which disregard the negative effects of debris, I think it would be fitting that debris get a nerf (buff?) to have similar effects to asteroids. The stress just simply isn't enough of a detriment any longer to allow ships to fire while on them. The crit roll for damage is still fine.
Now go ahead and let me know why this is a dumb idea.
Or, perhaps agree...? Ya... not likely, I know.