Why bother
What a person actually changes
AI stems arrive with everything at the same distance from you. Nothing is forward, nothing is behind, and the vocal sits on top of a wall rather than in front of a band. That is the tell, and no amount of loudness fixes it.
Mixing it by hand means deciding what the song is about and then making the arrangement agree with that decision. It means the low end stops competing with itself, the top end has air rather than fizz, and the vocal sounds like a person in a room. Those are judgement calls, which is the one thing a generator cannot make on your behalf.
If the song genuinely needs new parts played by people, that is a different job and a bigger one, and it lives at SongGenie rather than here.
Send me the song, free