"Both"
"At the same time"
"But also"
"It is not the only thing"
"It also includes"
"There are many systems"
Here is my current understanding of Arcen's policies regarding many things. As an indie company, making one game which specializes in one thing, and doing this one after another would make more sense I assume.
It has been a while since I saw a single game idea that is perfected so elegantly, that none of its components (like graphics, UI, tutorials, sounds) actually are in need to be justified by the "indie" phrase.
I hope this last game is more refined than the others, since solving overcomplexity problems, (and also solving bugs in a different setup in mind) will definitely tire you.
Although, if I understood you right, you will try to refine 7 days to die, which you love. Most of the charm of 3d games comes from immersion, which is tremendously aggravated by good 3d models. What I am trying to say is, as far as I know, indie community is less tolerant with not perfect graphics when it is in 3D. I guess you already considered this, but I just try to give you the initial feedback you are asking.
If you could make a game you love, and play with your wife, even that would be one of the biggest things a person can achieve. Just dont overreach, and dont add new mechanisms before perfecting the existing ones, and I am able to see something is great is shaping up. And yes, kickstarter is really a good idea to fund your business, since it is one of the sources I use for deciding whether to pick up some games after its release on steam. And you have many devoted fans (whose love will make mine look like tiny), I am sure that with enough tiers and different rewards (like naming a mech in the game etc.) you will be funded.
The only thing is release dates are one of the biggest problems that developers are faced there. So, dividing all tasks to do to be able to get playable games even after leaving some systems after release will definitely make sense.
I dont play 3d games mostly, but my wife likes survival games, and I will ask her opinion about the game when there are more information. For now, to my horror, it again looks like a risky project, but if you are sincere about comparing your hype for this to AI war, then we should all shut up