Great tutorial!
First of all, relatable. Coming up with an idea is hard, coming up with a good idea may be sometimes a quite hard step in the process of development.
I can add up an idea on how to make game ideas. This one may fit on the Edit Others’ Ideas, but here it goes. I like to call it…
The PPAP technique!
Yes, the name comes from the meme. Sorry. I brought a ded meme back to life.
Jokes aside, the concept is simple to figure out. Just blend together two game concepts. If the mix sounds good, then you’re ready to go. 
Let’s go to an example:
- I have a racing game;
- I have a Sci-Fi battle game;
- UGH!
- Racing in space!
Well, this was how I got my idea. Yes, I’m making a game based on this idea of racing in a space environment.
At least this worked for me 