Allen edmonds Strand Black or Bourbon
Black with dark conservative suits. Dark brown with anything. Bourbon with anything except a dark, conservative suit. Walnut with a light-colored suit, or in a 2008 issue of GQ.
Really, if biz cas is no jacket or tie, then you might want to look at a different style of shoe. I have them in dark brown, but I only wear them when I'm in at least a sportcoat, and more often then not a tie.
fancy compared to what? I thought broguing meant more casual? In terms of AE, formality goes from Park Ave > 5th Ave > Strand
Black to tone them down? I thought the formality in color went Black > Dark Brown > Burgundy > Bourbon > Walnut
Brown, brogued shoes stand out a bit more, though. There's formality, and there's notability. Having a pair of shoes that disappears under the hem of your suit is a good thing.
It's a balance. My dark brown Strands are my only AEs -- shoes I can wear for something serious, but which are still an elegant choice with a sportcoat. I bought them with confidence -- because I have uninspiring plain black captoes for when I need them. If I didn't have a pair of conservative black shoes, then I might have gone for PAs (even though I'm not a big fan of the PA).