Would it be acceptable to post an enormous, character-limit breaking pipe dream in the Game Design section? Because I've got one: A god-game called Kigen. (The first instalment being called Kigen: Genesis.) It's not something that I'm in any position to do and will not be any time in the foreseeable future, but it's something I want to do sometime in my life, and it is HUGE.

Is it possible? You can find out by attempting to post it.

Is it allowed? As long as you're not breaking any of our rules and it correctly fits the forum you're allowed to post it.

Is it a good idea? Probably not in one individual post. It'll be too big and cover too many different potential topics for most people to read or for there to be any meaningful discussion. You will probably have more success if you break it down into smaller sections which can be read and discussed individually. You can link them to each other if you feel the context is crucial.

Alternatively you could host the whole thing off site and link to it, but again unless you asked very specific and targeted questions when linking it would be likely to overwhelm people and get scattered and unfocused responses.

So, is it acceptable? I think that's a combination of the above responses; use your own discretion based on the above, but I think the answer is probably "yes, if handled correctly".