I've read your idea and I'm sorry to say it or maybe even disappoint you but that sounds like a project for a 25+ people full-time working team of professionals for at least 2 years, especially considering that you want to have top-notch visuals.
I know that you've said you try to think in the long-run but I try to save you a lot of time (that you will never get back) and frustration. Additionally, after some time, maybe even only weeks, you will probably get an idea for an even better game. What I find a little surprising is that you only talk about the gameplay, I would have expected that you write about the story first.