If you write a great melody to someone's lyric and you've been paid for it, then your part is a "work for hire". If the song sells a million the question would be, "How much would you be willing to pay a lawyer to try to prove you are due any of the royalties?".
My advice would be to find a lyricist and collaborate. THEN pitch your songs as a team.
Ultimately it's about the music anyway so you should be able to understand why your proposal has been offensive to the serious lyricists and composers in this group.
Just a thought.
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