Issues with Mei balance

I heard that it’s hard for her now that she doesn’t have her stunning ability. So that is just an idea but it would be cool if she had lower damage spraying lower parts of the body but more in upper part (most damage on head). The thing is that if she hold primary fire on lower part body for some time she could freeze someone to the ground with a short duration rooting. I think it would be balanced and fun to play choosing between higher damage or crowd control.