Those look great! The only thing I'd suggest is the MKII cover, on the spine has a vertical Acclaim logo instead of the horizontal SEGA logo.
And if you want to adjust to the strength of the colours in PS you can do it by going to Image > Adjust > Hue/Saturation and increase the Saturation a bit. It really makes the colours more vibrant. Also in Image > Adjust > Color Balance you can adjust the strength of certain colours.