Lovely colour and as mentioned looks very clean and uncluttered. Is that an eccentric b/b that tensions the chain?
Oh, and see what you say about the colour matched stem but for me a black stem to match the black post would emphasise the no nonsense build even more (although this is splitting hairs).
The BB is the Trickstuff Exzentriker - it does the job very well in my experience, the only negative point being that you don't have as much "throw" as with something like a Bushnell EBB, only enough to compensate for about 1/2" chain length in total, so depending on gearing and chainstay length some people might have to use a half link.
You're limited, of course, by how much a 24mm HT2 spindle can be moved "off centre" in a standard 1.37" BB shell. Allowing some clearance the theoretical maximum would be about 8mm, I think that the Exzentriker manages about 6mm.
Anyway, I can use 32:18 or 32:19 with no problems and I'm not likely to need to change that to anything else (unless I go to live somewhere like Lincolnshire or East Anglia, which isn't going to happen...)
Some might say that it seems an expensive way to achieve what a £15 tensioner would do, but having tried that way I think this is a big improvement. Looks (and is) a lot tidier, runs quietly (unlike some tensioners) and no chain clatter on bumpy, rocky descents (which spring loaded tensioners will still allow to an extent).
Also, "push-up" tensioners (like the Surly) can make it a pain to get the wheel in and out - I had to take the skewer out to do this. "Pull-down " would be easier in this respect, but that's not the way to go.
In my opinion the two best methods for SS chain tensioning are EBB or sliding vertical dropouts with integrated disc mount (Paragon, or for OEM stuff, Kona or VooDoo). I would have used the Paragon sliders, but the frame would have needed extensive re-working of the stay angles to keep the wheelbase where I wanted it to be.
Sorry - this is becoming another of my lengthy "essays" on SS philosophy.....
You could be right about the black stem, although I still like the colour matched one too. If I can find a black 70mm x 8 degree Thomson stem at a reasonable price I'll probably throw one of those on it. I only did the colour matched thing because it had "Ridgeback" written all over it....