I definitely agree that people are quicker to jump on Ranger for his mistakes than any other D-man. Other than maybe Phaneuf, but he's been pretty solid so people haven't been all over him.
But where people are harping on a few Ranger mistakes here and there I think you are equally praising his break out ability on one or two beauty outlets. There have been some STINKY turnovers, and if in transition if his excellent stick work doesn't bail him out (which it often does) he is TOAST because of how slow he is. His lack of footspeed also limits his d-zone breakout ability to mainly passing, whereas Rielly can both rush and pass.
Advanced stats I really don't have time to open a can of worms about. Lol. I am all for gathering and looking at data but I still don't think it's concrete. (And yes I know this is a craaaaazy hot topic right now) You use d-zone starts combined with least 5v5 GA as a praise point, I can counter with the possibility of d-zone starts increasing the likelihood of his team starting with the puck (ie - better faceoff man out there. McClement/Bozak vs Kadri). Is winning a draw in the D-zone less dangerous for a goal against than losing one in the O-zone? I have zero stats in front of me for Leafs faceoff percentages in zones, so perhaps that hypothetical argument is wrong, I'm just trying to illustrate that IMO Advanced Stats still don't show the whole story. But I am all for them and trying to learn from them. I'm certainly not one to grumble and say they're garbage and found the stats you listed very interesting.
From a non-statistical POV, watching every game with no bias toward a certain player (I want them all to play SPECTACULARLY!), I think it's crystal clear that Ranger has been the worst D-man. I hope he has a great game tonight. But watch when he turns the puck over. If he can't whack the puck away from the opposing player, he is toast. Rielly can chase that mofo down AND provide better puck rushing (maybe not passing) to exit the zone. Just my opinion.
GO LEAFS GO!