If Hasbro only understood board games then there would be no brony (My Little Pony) fandom. Any nebulous subject needs to be approached in a similar way to Hasbro's reboot of it's 80's (and much smaller and trite) property.
1. Find someone with both talent and passion for the subject.
2. Give them time to develop concept/treatment, allowing them to grow their own team.
3. Keep the restrictions minimal, and follow their lead
4, Avoid tailoring the project to fit merchandising, but let the merchandising follow the project closely.
5. At almost any cost, have the community there for each step, and keep the IP lawyers on a very short leash.
Allow profit to come in from licensing, sales, and make sure everyone involved never stops listening to the community. Not just doing what the community wants, but interacting with them and explain why major choices were made, whether popular or not.