I think you are aiming way too high for Scyther. Its choice sets might have potential to be decent, but the fact of the matter is Scyther is simply not that good in this metagame. Its weaknesses due to its typing are all pretty bad, especially a 4x Rock weakness, so it loses half of its HP to Stealth Rock. Now I know Moltres and Fletchinder both suffer this very problem as well, but they are much more threatening due to the former having nuclear power and Roost, and the latter has priority Acrobatics which is dope, as well as Will-O-Wisp. Scyther is not that threatening, especially since it has trouble taking on some of the prominent threats in this metagame. It absolutely needs Spin or Defog support and is not as rewarding as Moltres or Fletchinder with it, and it has a number of checks and counters such as Fletchinder, Mega Pidgeot, Emboar, Jolteon, and many others, all because Scyther's typing gives it so many weaknesses, and its movepool is not all that great and has somewhat average coverage. That being said, I could see it in C or C+ to say the very least because its CB set is a nice U-turn user that hits hard and fast and can give momentum, and its SD set might be okay with its bulk with Eviolite. But putting it in B+ is simply not okay, there is absolutely no way Scyther is on the same level as useful Pokemon such as Tyrantrum, Shiftry, and Registeel, let along lower B Rank mons such as Delphox, Mesprit, Clawitzer, Heliolisk, etc.
Sawk is cool and all but Montsegur just hit the nail on the head, it needs quite a lot of support compared to B+/A Rank mons. Plus it faces real competition even though its power, coverage, and abilities are all cool advantages over them.