I'll give you my brief opinions.
Gengar is fine. I've faced many of its sets and they are all terrifying. 130 Base SpA backed by a high Speed and access to two moves that make Substitute a nemace and easy unresisted coverage along with the Steel nerf makes it good. Its Scizor problem is less of a deal since no one uses Pursuit when Knock Off is available.
I want to say that Deoxys-D is amazing. It is more predictable than its Speed forme, but it is still one of the best leads in the game. Easy A+
Skarmory needs to be moved up to A Rank. Honestly, it gained and nothing has changed to weaken it other than some stupid Steel type nerf. It walls Mega Venusaur and Pinsir and phases out so many deadly threats in this metagame with ease, it is not even funny. It can also use Defog now and that typing and bulk makes it a good A candidate. Did I tell you that it hits hard with Brave Bird?
Finally, Gyarados should stay in its current ranking. M Gyarados is so dependent on luring Rotom-Wash with regular Gyarados, it's not even funny. I find myself being walled by a Skarmory instead of killing a Rotom-Wash because I M evolve to early. It's typing is great too and that typing lets you set up with ease for M Gyarados to kill. There are dependent on each other which should keep Gyarados in A. Even if you aren't using the M Gyarados, regular still has its merits since it can run a bulkier DD set or an LO set which hits ridiculously hard with Moxie. SubDD can set up DD to +6 on a non Thunderbolt Rotom-Wash and 2HKO it without taking major damage thanks to the Substitute.
Also, Conkeldurr, Terrakion, and Mandibuzz should move down to A- IMO.
Gengar is fine. I've faced many of its sets and they are all terrifying. 130 Base SpA backed by a high Speed and access to two moves that make Substitute a nemace and easy unresisted coverage along with the Steel nerf makes it good. Its Scizor problem is less of a deal since no one uses Pursuit when Knock Off is available.
I want to say that Deoxys-D is amazing. It is more predictable than its Speed forme, but it is still one of the best leads in the game. Easy A+
Skarmory needs to be moved up to A Rank. Honestly, it gained and nothing has changed to weaken it other than some stupid Steel type nerf. It walls Mega Venusaur and Pinsir and phases out so many deadly threats in this metagame with ease, it is not even funny. It can also use Defog now and that typing and bulk makes it a good A candidate. Did I tell you that it hits hard with Brave Bird?
Finally, Gyarados should stay in its current ranking. M Gyarados is so dependent on luring Rotom-Wash with regular Gyarados, it's not even funny. I find myself being walled by a Skarmory instead of killing a Rotom-Wash because I M evolve to early. It's typing is great too and that typing lets you set up with ease for M Gyarados to kill. There are dependent on each other which should keep Gyarados in A. Even if you aren't using the M Gyarados, regular still has its merits since it can run a bulkier DD set or an LO set which hits ridiculously hard with Moxie. SubDD can set up DD to +6 on a non Thunderbolt Rotom-Wash and 2HKO it without taking major damage thanks to the Substitute.
Also, Conkeldurr, Terrakion, and Mandibuzz should move down to A- IMO.