Here are some sample images taken with the Sigma 24mm f/2 Contemporary lens on Sony E-Mount. The clickable aperture ring is fantastic here, and the build quality and feel of the lens punches above its weight in cost. Very sharp images make this a solid choice for those looking for a wide-angle lens that's relatively fast at f/2.
The 90mm f/2.8 Contemporary lens is an affordable option from Sigma. The weight and balance of the lens speaks to a professional look and feel, but the price is less than what you might expect. Combine the quality of the optics with affordability and you have an attractive option for Sony's E-Mount system!