That stuff is also a pretty huge part of game design. Refining, optimizing, and unit balancing is how you get a fun game rather than just having something that's playable. Going on your own kickstarter and saying "I'm not mentally invested in things like unit balance" in a bloody strategy game is effectively shooting yourself in the face.
I think the biggest thing here is that Arcen has multiple people. Chris is now, effectively, the Engine/UI/UX guy. Keith does a lot of the balance coding. If it was just a team of one, I'd say he was shooting himself in the face, but with multiple people, I think its totally fine to say "This is my role, and I don't like to do this other stuff" even if that's a majority of the game. After all, he did say Keith was taking over the reins for the vast majority of the game. If Keith were to come out and be like "Yeah, I'm not interested in it either", then it would be suicide. As is, its honest and works due to division of labor.
So... why wasn't that the case before? It's not like there's suddenly *more* people, so emphasizing the seperation makes sense. I mean, how was it going to work before, that it's suddenly necessary to change it? Was Chris going to be doing all the stuff he apparently doesn't want to do? If not, who was? If it's the same arrangement it was before, why talk it up like it's some exciting new thing? There wasn't going to be division of labor with $300,000, but there is with $50,000?
Of course, this makes it clear the actual "make the gameplay work" part of the game is on Keith. If he changes jobs, the game doesn't sell well enough to keep him past release, or god forbid, gets injured, the other person who can do it just said he doesn't want to because he isn't interested in annoying things like balance patches. Talk about promoting faith in the long term support.
I've seen KS campaigns that were just timed wrong, designed poorly, and had bad luck. I've never seen one where the creator seems so intent on creating the impression that he'd rather be doing something else. It's utterly baffling.