To be honest, Larry, songwriters trying to sell songs sell the SONG, not the production. Few artists want to cover a songwriter's demo down to the note. A LOT of great songs are sold with no more than a piano or guitar and a vocal. Let the producer decide what HE wants to do with it (or the artist). Leave them nowhere to run with it, you put yourself at risk that, if they don't like the production, they don't like the song...
If you played this song on piano for an A&R guy, it's his JOB to hear in his mind how incredible this could sound
But when he adds it in his mind, he is adding what HE wants to hear it like, not having it spoon fed to him and risk him not liking the production...
Have you ever been to singer songwriter 'circles'? A few songwriters get together, play tunes they have written, talk about the craft... They don't bring in bands, they don't bring in tracks, they sit around on stools and either play guitar or piano and SING. THAT is songwriting. You are confusing it with record production... They are two different things, at different stages in a song's release.
You need to be very careful not confusing the two. Chose what you want to do. They both take a lot of time. Spend days or weeks polishing production values, and that is days or weeks you HAVEN'T spent writing. And vice versa. You are getting there, Larry. It is perhaps time to reflect realistically (none of us is ever going to be Steely Dan!
) on what you DO want to do, and go for it. Shotgun yourself around on several different disciplines, and you may miss the boat on any one of them...