I get his OCD - it's pretty much a basic job requirement for what I do for a living - and sustaining it for decades isn't a problem, if you like what you're doing.
It looks like he's gonna get a break for the next update anyway - it looks like we're gonna get a story line about Zoey, which will give him time to create whole new environments, characters, settings, etc. Just the thing for the middle of a big project. And, if it were me, it would be a good place to do a shorter update, since she's not the main character of the game, and he probably just has to give enough of her back story that having her show up will make sense. Sort of like the flash backs at the begining of episodes, but a bit longer. I mean, it's a guess, but it would make sense.