Can't really comment on this season because I haven't seen it yet, but this is valid, OP. Every season is a roll of the dice when it comes to choosing the right people and having them all work well together in a way that's fun to watch. It'd be weird if they never got it wrong. I know there have been seasons that were less memorable because of casting choices, and sometimes because the tasks seems a bit less inspired... which is also only natural as time goes on. But overall, it's a great format for a show and there's always the potential for next season to be better, so I just shrug and move on.