The software here gives you all the time you want to post something, but a limited time to edit, so it is highly desirable to know exactly what you want to say before you hit "Submit."
I am afraid you might have some difficulty finding collaborators here. Most writers -- and certain the vast majority on these forums -- prefer to work on their own ideas (of which they have many) rather than on somebody else's.
But you don't have to be perfect to finish your project on your own. You just have to be dedicated enough to stick with it. If, after a lot of thought, you decide that you don't have that kind of commitment to what you already have, it's unlikely you'll be able to convince other people that they should. If you don't love it enough to stay with it, then maybe it isn't that good. Even if it is that good, if you've run out of enthusiasm, it will be hard to ignite enthusiasm in others.
Why not give it a while longer?