Sorry for the radio silence everyone, I truly apologize.
I updated the OP with:
Mega Pinsir to
B
Sableye to
B-
Mega Aggron to
B
Both Gyarados to
A
Mega Luke to
A-; It's a glass cannon in the truest sense of the word and while it's strong, it's not always a practical choice in a meta that is favorable to bulky offense. Base form having terrible speed for something so frail is a major con as well. Even regular Mawile has better opportunities to get on the field than Luke. Not trying to be all doom and gloom but I believe that it deserves A- rather than A or A+.
Tyranitar to
A; I'm not the greatest fan and has common weaknesses but DD Megatar is a monster after just one boost and is one of the better anti-weather in the meta. Really, for most special threats especially those that don't run Focus Blast for coverage, Tyranitar is generally a good starting point as a check.
Landorus-T to
A; hasn't really been talked about but remains one of the best users of Scarf in the meta imo along with being a great Intimidator.
With that,
Montsegur, I believe all of the most common mons have been addressed except for maybe Greninja, but I am too biased to make a judgment on that one lol. I don't think it's the worst mon but definitely something extremely prone to being used improperly so I'm going to defer that one to others.
Regarding Dragonite: I would agree with it in
B+, the reason being that it doesn't offer the fantastic dual-STAB that Garchomp does. SD Chomp does run Outrage but the important thing is that it has the option to weaken potential Outrage soaks with EQ whereas Dragonite can't necessarily do that after only a DD. ES is fun but not the best tradeoff for this, although Dragonite does significantly better against the lot of frail and fragile mons. That being said, I think that Weakness Policy is underutilized, it's the best user after Aegi and even if you get rid of Multiscale, it can soak one of the multitudes of weaker non-STAB HP Ice/Rock Slide/etc.
Blurbs will come as I can make them but if anyone has further input, lemme know.