They could've had her in a modification of her original costume, which could've been just a female version of Captain Marvel's classic costume:
Instead of her bare legs showing, she could've had red on her legs like Captain Marvel, making it a full bodysuit.
The dominant colour would've been red, with some blue (or black) parts.
That would've been more interesting than what we got.
Marvel can't seem to steer away from the same design elements they keep using. They even put some of that on Spider-Man's costume with those black lines on his legs.