So nano banana is insanely good for pose control and targeted edits.
The caveat for one thing is that it lowers the resolution of the original image, fine that can be fixed with a run through an upscaler
The second thing which is significantly more difficult to fix eye color/consistency. Generate an image of a person, run any change through nano banana and you will notice that the eye color/detail gets demolished.
Perhaps the fix for this is an inpaint option where you can highlight the parts of the photo which must NOT be changed.