I just reached DC. I left most of my best mats behind thinking, for various reasons (such as the fishing quest, presence of multiple inactive elevators, etc), that I would be able to return without too much trouble. In particular I saved my best Super Steel to infuse an Ancient Rathound skin. Well, it seems I might be stuck down there till the conclusion, and with no home workbenches, suddenly all those new and exotic mats down there are useless to me.
[minor spoiler ahead] The Faceless leader tells me an elevator leads to the surface and I need to power it via the old Power Station. That power station appears to be one giant puzzle, but OK. However, various hints, clues and a squinty peek at the wiki (trying to ONLY glean what I absolutely need spoilers-wise, no more, so please keep answers in that vein as well) I suspect that I might be finishing the game down here before I can return. Am I right? Or can I get back up to my house fairly quickly, then return to finish the game. If not, I'm reloading and pumping my crafting skills to the maximum even if I have to neglect everything else. I couldn't believe my luck when, just as I was complaining about mats quality, I got a 160 Super Steel! It's not doing me any good in a closet though