Mining need not scar a fortress aesthetically!
Take for example this [hypothetical] map of Moria:
Notice how the rough tunnels bleed into the main thoroughfares, and indeed form labyrinthine caverns themselves. Mostly at the edges of the Kingdom of course, but also in the deeper, orc-infested areas. They remain rough and wild without affecting the majesty of the more civilized parts (although Moria is of course, described as pillaged and desecrated).
Take next, this map of Hollownest:
Yes 2d sidescroller, I know, but observe the construction of the Kingdom. A great city in the center connected to ever smaller and more exotic villages, often ravaged by uncharted or wild tunnels. There is also to consider the BORDER of the Kingdom. You could simply designate an area that is primarily for building and mine outside of that area, either literally separating the kingdom proper from the mines with a subterranean moat, or simple doors and gates.
The main thoroughfares tend to be near the surface where visitors may more easily make their way to the interior of the kingdom. They tend to be largely disconnected from nearby wilderness and mines (aside from the main entrances to those places) presumable for safety. You might consider keeping your constructions and mining operations separate entirely, connecting all locations via one travel tunnel (like the Stagways of Hollow Knight).
The point is, there are ALOT of options to keep your mining aesthetic. None of them probably good for FPS, but that be the price to pay for pretty looking Dwarf Kindoms.