What were among the most impressive buildings beside cathedrals in medieval towns? Guild halls. Massive, opulent buildings erected for the sole purpouse of showing off how filthy rich and important the guild is.
Guild leaders should not only demand a phat bling-bling crib for themselves, they ought to demand a mad pimping guild hall for their posse, yo.
The guild hall is like a little fortress to itself, containing at the very least a massive dining hall, an equally massive gathering hall, rooms for the guild members (who would then pay rent to the guild, which pays rent to the fortress, i.e. the player) and whatever they need to show off their guild's importance.
This is where all the legendary masterpieces of the guild members go, in the big hall filled with carvings and statues of prominent guild members (and this is where you want to break in as adventurer... )
I imagine a miner's guild hall would be a series of huge natural caverns, completely unadorned (that's for those pansy-schmansy masons) and just a massive display of mining skill. Natural pillars and... uh... stuff. Maybe huge piles of ore? I dunno. A big display of the worn-out picks of master miners?
The craftsdwarves guild hall would probably be obscenely, filthy stuffed with lucre. Oh, yes. And then a human thief gets in, and then there's 4000 years of war.