Bunker 2 has a very post-apocalyptic feel to it. Should I accoustic treat it, light it, and shoot videos against the concrete walls as a backdrop? If so, what videos?

Unless ofcourse you want to open up a home improvement Youtube channel: how to make an ugly storage room useful as an office.
PS: there is a treasure map stuck behind that pipe. Maybe X marks the spot
It looks a bit too dark and dingy in there to be making videos, whilst it's still empty I would run a sealer over the walls and then give them a good coat or two of white wash just to brighten the place up a bit.
It looks a bit too dark and dingy in there to be making videos, whilst it's still empty I would run a sealer over the walls and then give them a good coat or two of white wash just to brighten the place up a bit. 
You underestimate the power of studio lighting and the sheer number of spare LED panels I have.
The walls look absolutely terrible......dreary and old......give them a freshen up. Will make for better videos visually.
IMHO.
Ian.
Regarding getting internet down there, so long as its one continuous cable (no patch panels or keystones), 100meg and even gigE can easily go >150m on decent quality cat5e. Shielded might be worth it if you're really pushing the length and lots of the run is parallel to other coms cables, but that comes with it's own problems.
The walls look absolutely terrible......dreary and old......
That's the
entire point of this thread. Looks so bad, it's cool.
Should I accoustic treat it, light it, and shoot videos against the concrete walls as a backdrop? If so, what videos?
Yes, you should. For practical reasons, you’d want to avoid videos that utilize lab equipment. Therefore, the most obvious videos to shoot there would be mailbag videos. When there’s a teardown segment within, those parts could be shot upstairs, but the majority could be handled in the bunker.
I suppose if you got a hot plate, you could also start doing introductory cooking videos down there where you simply dumped cans of things into pots.
Should I accoustic treat it, light it, and shoot videos against the concrete walls as a backdrop? If so, what videos?
Yes, you should. For practical reasons, you’d want to avoid videos that utilize lab equipment. Therefore, the most obvious videos to shoot there would be mailbag videos. When there’s a teardown segment within, those parts could be shot upstairs, but the majority could be handled in the bunker.
I suppose if you got a hot plate, you could also start doing introductory cooking videos down there where you simply dumped cans of things into pots. 
Mailbag? He went to a lot of effort to put a giant TV behind him for mailbag videos so they would not be the best choice. Before that it was corner or no corner. And, it might be everyone's favourite video but there's still only been three this year by my count. I'd pick some other type of video.
The only reasons I can see to get excited about shooting videos in the bunker would be to either avoid moving the heavy stuff or to classify use of the bunker as a tax deduction.
Even the post apocalyptic inventor doesn't worry about backgrounds that look cool. Repairing societies junk is cool. Trying to look cool is ironically not actually cool.
If I look through the list of channels I subscribe to only a few have ever mentioned the background. Mostly It seems to be the precursor of a relevance bypass operation when the background becomes the focus of interest.
How about an EEVblog meetup while it is still relatively empty?
He went to a lot of effort to put a giant TV behind him for mailbag videos so they would not be the best choice. Before that it was corner or no corner.
That’s surely only because Dave didn’t have access to this amazing bunker at the time!

Seriously, though, using the lab as a lab and moving incoming packages to the bunker makes a lot of organizational sense to me.
How about an EEVblog meetup while it is still relatively empty? 
We can all sit around the infinite power ring and chant Oooohm Oooohm
We can all sit around the infinite power ring and chant Oooohm Oooohm

Well done for your solution to the function shown in the engineering diagram with the complexity in Big O notation.