i'm waiting for someone to complain about the bokeh....
The bokeh is crap and my Canon 50L clearly kicks your Sigma 50A's butt
I'm just kidding!!! Those are great shots and the sharpness, color, and contrast are all excellent. Since you mentioned bokeh, here is my subjective
opinion on the subject.
Overall, the bokeh is very pleasing and soft, and in 20140429-13.jpg, the bokeh is especially impressive on the Buddha head in background on the left. Point light sources look to be handled very well (good flare resistance, too).
In the negative column (and this is being picky), the rear bokeh of the defocused necklaces in 20140429-29.jpg and abacus beads in 20140429-47.jpg has a bit too much contrast in the "transition zone" and comes out a little harsh IMHO. The front bokeh transition zone in 20140429-32.jpg is handled better and is a bit softer.
Compared to the 50L, I would say that the bokeh is a bit smaller in diameter, has more contrast and is just a tad less smooth in the transition zone. I think the sharpness and price more than make up for what appear to be very minor differences.
Based on these images, I would say that (possible AF issues aside), Sigma has a winner on their hands. Thanks for posting the photos and congrats on the new lens!