It is hard to get a killer app in any space these days since the field is full of very talented developers.
I personally like the way Hype is going. If they were just a Game Development platform that would be too limiting to their growth.
The fact that I can prototype projects or make real projects that sell is a bonus for me.
In the end I am a Hype Evangelist I guess. I see real potential in the application as it stands today and cannot wait for more updates.
As for Game Development alone…
I am a digital illustrator hybrid by training, and while that helps me with my projects.
For those that are not illustrators there are several repositories for buying sprite graphics for use in Hype or other platforms.
While we illustrators like to get freelance work too the repositories are great places to get your backgrounds, sprites, and platforms for example…
It still supports illustrators as well since they can sell their asset packs using sites like these.
Also let’s face it if you want to develop games then it is a full time pursuit either as a day job or a second freelance gig.
I would suggest GameSalad, or Unity for that or even YoYoGames.
The other site you should look at is RayWenderlich.com
He has some of the better tutorials out there for game development and iOS development.
And good luck on your next project!