The marketing of the game gives me honest concern. It is the quintessential "list of features" that is indicative of technology made without acknowledging a critical, artistic perspective - that's even true of the title "Voxel Quest." If you can correct this and gain understanding of what the game _represents_ and what areas you _want_ it to be critiqued on, it will become both easier to design and to market. Narrowing always clarifies things.
There is one aspect in which you do show a definite perspective, and that is in the use of a simulationist philosophy: Everything done in deterministic, procedural, emergent ways. Now, one of the ways in which this philosophy gets challenged is the issue of "you don't know what you don't know" - if your simulation is built upon bad premises, then it's garbage in, garbage out.
So then, if you want to find the same kind of successes with the approach as something like Dwarf Fortress, Spelunky or Minecraft, you have to actively acknowledge where your simulation becomes intentionalized by the assumptions you make about how the world works. At that point you are in the business of making critical arguments through your game and the workings of its systems: Things like how the economy is tuned, frequency of combat, or average NPC reactions to violence, all send unavoidable messages about the totality of the world you make.
You can literally pick just _one_ thing that characterizes the world, consider it in depth and tailor every other system's features around it, and have a fine game. Even Dwarf Fortress, which is extremely deep, shows intentionality in that the details it focuses on are descriptive and categorical(types of rocks, individual organs) vs., for example, being spatially accurate like the physics simulation of a racing game. What makes DF's detail cool - and what makes it a big, complex game instead of a tiny one - isn't that it attains atomic precision, but that everything adds up to a specific, detailed, believable narrative about fantasy characters doing the "everyday things" we expect to see in a fantasy world.
To put it another way: Eliminating things from the game makes it impossible to criticize those things, and every game eliminates something! But the things a game does show should have a ton of care put into them.
If you're doing all of this right, you'll be up at night with some fear over the internal struggle of the design decisions, instead of the actual production or marketing; you are already demonstrating the necessary skill to do those two - you have very nice graphics to show off in your trailers, which is a great entry point.
The only reason why the marketing looks hard is because there's a lack of design intent, and thus nothing but bullet point features after you show the graphics. But the design can act as a master plan for the marketing, as it allows you to go on at length about the things being conveyed through the systems, vs. what the systems are, where your effort on details is going to go, and how you want the overall play experience to expand over the coming months.