I thought your essay on Lil' Beethoven was alright, and I think that, even if the album isn't intentionally structured to reflect the "story" you construct (which you yourself admit it probably isn't) you have identified many of the important themes underlying Sparks' music at this point in their career.
My only problem with that is that understanding Sparks makes me like and respect them less.
So they wanted to be famous pop stars and it didn't happen. Boo-ho. What's "emotionally devastating" about that? Leave aside the issue of whether they deserved bigger success or not (I'd say their unpleasant and snarky attitude didn't exactly help). I still don't see why I should really care. Two spoiled middle-aged former fashion models complaining that they only had 15 minutes in the spotlight. If they took it all in stride, and weren't so bitter about it, that'd be one thing, but acerbic solipsism is not my kind of thing at all.