Well, there are changes, and then there's shoehorning... Both teams Marvel has in their movies absolutely prioritized the characters that were relevant to the stories and/or period of comics they were adapting. ALL characters on GOTG are founding members of DnA's run, and we know some of the remaining characters from that run are also likely to come before any other unrelated character. The Avengers have had MANY rosters, but Marvel obviously chose to prioritize characters from the Lee/Kirby era, which makes sense. They even planned for Ant-Man and Wasp to be founding members, something that only didn't happen because of the problems they had with the Ant-Man movie.
So I understand changes being made to YA in the MCU, but I'm still expecting the characters related to that franchise and/or that period of comics to be a priority over someone like Ms. Marvel. Not to mention their publication history is much smaller compared to the Avengers, so it would be easier to choose to focus on characters from that single run, just like it was with GOTG. Plus, Kamala has a lot more to bring to a franchise like Champions, because not only it's her established habitat in the comics, but she wouldn't feel as redundant, as the YA already have a Captain Marvel shapeshifting legacy AND a size-changing hero. And if they absolutely HAVE to make changes, then I believe those changes should reflect the franchise. Like, if they can't use Eli Bradley because of his comic book rights, then it makes sense to put America Chavez to replace him, because she has a history with the group, her origin story is directly related to one of the founding members AND she has the looks to be the ''patriotic'' figure of the group. That would be a change from the source material, but it would be more reasonable than to think Kamala would be the first natural choice to replace him.
At the end of the day, it all comes down to personal preference. Like I said, I'm very passionate about this particular group, so I want their live action version to be as close to what I'm invested on as possible.
I agree that a lot of her story would develop better on a serial narrative, but like I said just above, budget could and probably would be a problem. A solo show would have to put Kamala front and center as a hero, which means her powers would have to be the ones displayed the most. The Flash already struggles with the special effects for Elongated Man's powers, and he's not even the main star of the show. I wouldn't be against it, but Marvel Television would REALLY have to step up their game to make it visually appealing. No Inhumans level of cheap production, please.