Trying to be as reasonable and non-biased as possible here but...
Scrummaging - Should be great. Strongest possible unit, more or less.
Lineout - Youngs has - just about - been the form throwing hooker to date, but now he's dropped. Heaslip has been a major lineout target, dropped too. We've radically altered it, and not for the better. We now have no back rows who are used as regular lineout targets starting, and the weakest of the possible regular targets on the bench if we need to change it. Parling and Hibbard have been hung out to dry on this one.
Breakdown - I rate O'Brien, but he's not as good a groundhog as Warburton or Tipuric. We've also dropped the best jackal in the backs. None of the tight five forwards are particularly noted for their abilities here. At least we can change things a little with Cole and Tipuric. I'd say our breakdown capabilities have also gone down
Ball Carrying - Positive news with Roberts, O'Brien and Faletau all upgrades on the men they are replacing. Hopefully that will make a difference.
Leadership - We've lost our captain and also dropped one of the most (presumably) respected men in the team, as well as another guy with good leadership credentials. If AWJ gets injured or goes silent, who takes over? Roberts? Philips? Parling maybe? No leaders on the bench either.
While the changes probably do give us a better chance of executing Gatball and winning the game exclusively from the tight, we don't really seem to have any plan B, and will be executing it with a lack of leadership and a rickety set piece in the lineout. I also feel our defence looks a lesser beast on paper without Warburton and O'Driscoll. I am struggling to be optimistic and believe our best hope of winning lies in "accidentally" knocking on the ball every time we get within 40m of their posts.