[@Patches] Not trying to be a jerk or condescending, far from it however from my experience and from what others have done here is some advice:

1. Ever considered a Co-GM? It might sound silly for a free to casual game but I think if work is your issue you can get one that runs "the daily maintenance" when you deal with the actual story.
2. Sadly I know the feeling from both a player and a GM side. One of the reasons I pitch so many games now isn't due to me being obsessed with RPing but more due to the fact I want at least one going and most tend to die quickly
3. Interest is easy, it's keeping that interest going that's difficult

And I figured they would conflict of course just no mustache twirling bad guy lol.