I'm not so sure about this. Though I'm not a big fan of Hobbs, I don't think he is as bad as his form this season suggests. I can't imagine it is easy playing at first-five in a team like the Blues! Likewise, though Noakes looked ok this season, you have to remember he did have Aaron Smith inside him who seems to have the ability to make any 10 look good. When Hobbs was down at the Highlanders a couple of seasons ago he actually looked pretty comfortable at Super Rugby level (at least as comfortable as Noakes IMO). I really don't see much between Hobbs and Noakes in terms of ability - Noakes has the stronger kicking game and controls the game better, but does stand a bit deep (which makes the backline attack far less effective), whereas Hobbs plays a lot flatter, is a better ball runner, and a far better defender.
I just don't really see the point of having Noakes on the bench if you have Anscombe starting, as I like my subs to be able to make an impact or change the game in some way. There wouldn't really be any point in bringing on Noakes to replace Anscombe (unless Anscombe got injured), as they play a very similar style (except Anscombe is the better player) - all you would be doing is downgrading your 10. While there is no doubt you would be downgrading your 10 too if you brought Hobbs on to replace Anscombe, at least Hobbs has the ability to change up the gameplan (by playing a lot flatter on attack), and is able to cover multiple positions. If Anscombe were to get injured I would prefer Noakes over Hobbs as a starting 10 though. I suppose we will see how they both go next season!