I've noticed something in my broader stream.
It's full of a very specific type of failure. Do you know what I mean?
Can you name a single creative from the modern era, who only produced one "great" work?
I see many, many, people in my stream who talk about how they have been working on their 'great' project for years. Sometimes these projects even finally get published, to the great unwashed "MEH" of the internet.
Design is an iterative process. Not great design. Just Design. If you're spending all your time working on your great novel, or your role-playing game, or your board game, or whatever, but you never actually produce anything usable then you cannot grow as a designer. Your work will remain tepid.
The thing is, the idea isn't that great. Really, it's been done before. And it's quite likely you are doing it badly. I say this with a great deal of confidence, because you can't even begin to do it well, until you have a few dozen examples of your work under your belt.
You see, the elevator pitches for the Cohen brothers movies are terrible. "A divorce lawyer and a gold digger fall in love", "We retell the odyssey using 19th century criminals", "A stoned bowler gets mistaken for a different person". No world saving, huge action, robots, or secret to be exposed lies in those plots. Just interesting things done well.
That's key. The idea will not carry you through poor execution. Think about the designers you like, and notice how they are constantly producing things. Also, notice how they are successful. So do things, release them, and repeat until they are done well. Also, for goodness sake, please stop posting about what you are going to do and why you aren't doing it!