Was there ever a consensus on where Mega Blastoise belongs? I can see that it was mentioned several times but the thread's just too damn big to dig through.
I talked about Mega-Blastoise at one point before. I think I discussed its placing to be
B; while it is one of the best Spinners, it may or may not be worth the Mega-slot and doesn't have any recovery. At least it can still tank and / or hurt stuff when not spinning, unlike most spinners not named Excadrill and Starmie.
As for Salamence, I think I'd put it in
B-. It faces too much competition with other Dragons in anything it does: DD Mence is often outperformed by Dragonite, XZard, and even Zygarde; Choiced sets compete with Garchomp which has another form of spammable STAB and has a better speed tier; Latios and Goodra have better offensive stats / defensive stats respectively than special attacking Mence; even wallbreaking sets compete with Hydreigon,
also due to the latter's alternate STAB. The only set I can think of that isn't outclassed by other Dragons is some sort of special attacking Intimidate + Roost set which Dragonite cannot pull off as well. Don't get me wrong, Salamence can still be effective, but I don't see much reason to use it over other Dragons.
Hydreigon is still a fearsome wallbreaker of a Dragon, threatening almost anything, even some of the Fairies, for big damage. Fairies still throw a wrench into Hydreigon's wrecking days, but the Steel nerf means Hydreigon can alleviate some of its worries about Steel-types, unlike other Dragons who still have to deal with both. Hydreigon has the speed to outrun pretty much all bulky Pokemon, it is bulky enough to take weaker neutral hits and heal them off with Roost, and has the mixed offenses and movepool to threaten a huge variety of Pokemon. While Draco Meteor got nerfed in power, Dark Pulse became easier to spam (other Dragons do not have such a luxury), and it has both Flash Cannon and Iron Tail whose usefulness depends on how popular the trend of physically bulky Fairies are, meaning it can easily adapt to them. Of course, Hydreigon still has moves such as Fire Blast, Earthquake, and Superpower to demolish certain foes that Lati@s cannot best (tbh, Lati@s would probably be relegated to 'speedy offensive Defog user' rather than 'notorious special attacker' at this point). It's not too fantastic against offensive teams, but can still greatly trouble them if it gets the chance to attack. I can probably draw comparisons to
Goodra at this point, trading bulk for better wallbreaking ability, which imo lands Hydra at
B or
B+.
Edit: I just noticed Starmie is absent from the rankings as well. Being outperformed by Greninja at a sweeping role has probably hurt its viability, leaving spinning as its sole untouched niche especially considering Starmie's speed. It can either use a LO Analytic set which smashes spinners and retains great offensive presence, or it can use a bulkier Recover set with Scald for better survivability, letting it spin many times over the course of battle. Sadly, its vulnerability to Ghost (and Grass) moves means Starmie has to predict well to spin successfully or risk getting forced out / failing to spin which decreases its effectiveness, but I think
B+ is still pretty solid for Starmie due to its versatility.