I think Walker is pretty good, very safe, good runner and can pass the ball which he has shown a few times, the issue for me if that the rest of the pivots are poor, Trueman aside, Charles isn't ready, not only he isn't ready physically he is too slow with his decision making, he will get a lot more time in the reserves/academy to develop that side of his game and get some confidence.
Houghton's passing and decision making is shocking, best part of his game now is his kicking, even defensively he misses a lot more than he use too, lots of head knocks too, should have retired last year, time to give him a rest or reduce his gametime.
Cator has to be worst attacking 13, I've every seen, he link up play, passing is poor, never makes a break. Last season in 26 games he had no trys or assists and currently in 6 games the same. 32 games with a try or assist.
Adding in a 7, 9 and 13 of better quality will help the likes of Walker and Trueman.