ISO 400 is unnecessary in the full light of the day. The high ISO is making the photo soft. Try ISO 100-160 (camera dependent) (sometimes it's "ISO-Lo" or something like that) and compensate with bringing the shutter speed down a bit. Shutter 1250 or 1600 is normally all you need. The high ISO might have made the photo impossible to sharpen to the point that is acceptable for JP, simply because the subject doesn't fill the whole frame.

Practice makes perfect, my friend!