You Don't Have to Publish That Thing
On the matter of the blorbos in your head, here's a piece of advice you might want to follow or disregard completely: you don't have to let them out.
Let's say you want to make a game. You want to write a book. You have your OCs you love dearly1, but everything you have in mind mostly exists right there. I'm a firm believer that if you just keep on polishing an idea forever no one will ever see it, and that sucks; lately I've come to think a bit differently and question the why.
I've made quite a few games in my lifetime, written some stories, came up with plenty of fiction. A good chunk of what I've done has an unpleasant association with it: the productivity mindset that made me release them by cutting corners where I thought it made sense. I'm proud of this skill of mine, but too much of it leads to never caring enough for what you believe in, and that sucks a lot more than never releasing the thing. It's why I'm so burnt out from game dev (together with a number of reasons I won't share in public).
When I say "you don't have to publish that thing" I'm being a huge hypocrite: I love when others share their own thing. I want my friends' stories to be known to the world, I wish there was a place for all the stories I've been told as a "I'd make a game like this if I could, it'd be cool", heck I'd make them all myself just to put them out for more people to enjoy. I fall in love with my friends' worlds very easily. If I think of mine, though, I realise that in my chase to make them known to the world I lose myself in the picture, and what matters most risks getting lost.
Ask yourself why you want to do it, and why you want to finish it. I think finishing projects is extremely important (especially for professionals, but I'm speaking mostly of hobbies here), but some things can be just your own plaything forever. Show some comics sometimes, make a thread about your dream game while you work on its systems at your own pace. Don't forget you're free to choose when and how you want to play with dolls, and when and how you want to set up a stage. You can always do both.
Why are they even your OCs if you don't?↩