Moon Girl didn't have a fanbase when it just started. That was something that grew with time. Heck, J.K. Rowling's Harry Potter got rejected a couple of times - there was supposedly no market for it.
Creating books that appeal to the "Tumblr crowd" is all well and good. Heck, I started reading Vision and the ill-fated Mockingbird due to Tumblr recs. However, the delivery mechanism and pricing needs to be accessible to the target audience. That quite likely means Marvel Unlimited, comiXology Unlimited, bite-sized $0.99 digital issues or go straight to TPBs which can be easily purchased through Amazon, Barnes & Noble, etc. Not $3.99-5.99 single issues. Now if by some chance the new readers do start buying singles at $3.99+ a pop, for goodness' sake don't try to force them into buying a lot more books than they signed up for by tying in the book they're buying to an event or crossover.
http://www.syfy.com/syfywire/black-p...are-struggling
Marvel's trying digital subscription first now with Immortal Iron Fists which I think is a good move. Based on the art and the Mean Girls scene, I reckon this book probably isn't one that would have found success as a direct market floppy.