Yeah I had the same kind of impression of the book overall! Once it got going with the mystery I couldn't put it down.

Ideas are a dime a dozen, the really rare thing is project management skills that let you carry them all out at a reasonable rate!

I don't know if I would recommend Time Paradox Ghostwriter but it is only 14 chapters and on the shonen jump app/viz media website if you're really curious what it looks like. Pros: believes girls can make action shonen manga. Cons: just not smart enough to make the tricky premise work.