Here's how Tarkin looks in Lee Thorogood's Technicolor rendering, for comparison:
http://imageshack.us/f/543/vlcsnap2011121716h17m27.png/
I think you've brought him to life more with this adjustment, and he comes out different to Harmy's colouring as discussed in the despecialized thread, it seems this goes more in a reddish face direction than yellow (or grey)