I only adjusted the "Amount" slider in the "Lens Corrections" panel and was looking mostly at the white/dark borders. A little more time spent fine tuning things may have produced better results. There is still a light halo on the border, but at least it's not colored. How much is this image magnified? Too much pixel peeping can frustrate you!
Most of the editing you will need to do, including sharpening, doesn't really degrade the final image, it improves it, unless carried too far, of course.