I'm not sure how big are you willing to make this project , and I'm not sure if you can fully write the game with WebGL and what you mentioned because something may require some advanced stuff like Unity or Unreal engines.
So my idea is to make an MMORPG for mining bitcoin , users have characters on the games (and they can meet each others = multiplayer) and they should buy mining equipment's to mine obviously (using in-game currency that you should decide how they will get it on the first place) ... or without buying real miners , they should go to the mine and mine them with their hands . this is just the basic idea and since you said it should be related to crypto I guess that's the only logical idea .
In the other hand , I can give you other idea or give you more details about the above idea but I should understand what are you looking to get after making this game ? I mean are you willing to make it Free-to-play ? gain some profit like faucets etc ... ?
Maybe, I was misunderstood.
The core idea is ready. We're looking for a person who could help us implement it (not coding or design) - improve gaming models and ideas, texts (jokes about crypto for example) etc.