Sharpening seems OK in the Lightbox view. All those little bits on the ground may have an overall appearance of looking slightly over sharpened but the main elements seem to be OK.
Maybe you could try darkening the shadows a fraction to give more contrast, but be careful. There are a few rather dark shadows already there and these could easily become clipped.
Sharpening, as previously mentioned, is something of a personal taste and different people apply it in different ways. For example, typical sharpening with me is about 1 pixel at 25 amount and 50-60 detail with 10 threshold in ACR followed by Unsharp Mask in Photoshop with amount 40-50 radius 2 and threshold 2.
But, other people may well use different values. There doesn't seem to be any definite rules with sharpening just rough guidelines.