Masters isn't a replacement for Kennedy. To be honest it's probably neutral neither one really brought anything to the table.
I hope he has improved being overseas but I won't be surprised if he hasn't. Depending on what she he goes on I can see him working at the mid-card level. He would probably benefit more for ECW (more TV time) then the other two shows and get "lost in the shuffle."
I think they are prepared Mark Henry for a face turn at least in the summertime and what wouldn't be better then the world's strongest man vs. the masterpiece. It doesn't scream ratings to me, but since Henry has improved his work and Masters has gone to Japan you can only hope.