TFW this was originally supposed to happen on Friday or something but Omari got the thread locked two minutes before you were gonna post this so you got cockblocked:
First off, I don't think Kingdra should drop to C+ yet. In fact, I think I'd sooner argue for a Qwilfish rise than to drop Kingdra right now, since Rain has seen a good amount of usage and success on the ladder in light of OLT and Kingdra is usually a staple of rain to cover things that deal with Mega Swampert. I don't think it's amazing, of course, but I feel that, with rain being as good as it is right now, it's definitely a little better than C+.
I think Reuniclus should definitely rise to A-. I haven't seen it particularly OFTEN on the ladder, but when I've seen it I've really had some problems with it. It has a fantastic combination of great bulk, good coverage, good power, reliable recovery, and an incredible ability that lets it function as a powerful wincon. Reuniclus is another one of those things that is significantly better than its tiering would let on, and I think it deserves a place among the A-ranks since it has a lot to differentiate it from other Psychics in this tier.
Likewise, I think Blacephalon should rise to B, and I think Serperior should rise to B+. I'm putting these two together because they've seen a surprising amount of usage in OLT and are great on various offensive teams. Blacephalon started out as one of those massively overhyped threats and it got so bad that it became massively slept-on. It has an array of different sets, such as two different SubCM sets (SpA boosting and Speed boosting are both pretty good), Specs, which hits like a nuke from orbit (pretty sure basically nothing that doesn't have absurd special bulk, or an outright immunity to Mind Blown, has any real business taking a hit from it) and can cripple potential switchins with Trick (I actually misspelled this just now lmao), or Scarf, which trades a lot of the Specs set's firepower for better revenge killing abilities and... still being able to cripple stuff. Serperior, on the other hand, has been a real pain in the ass to deal with: I find its best and most consistent set to be a SubSeed+Glare set since it does a fantastic job of setting up on bulkier teams whilst being able to cripple faster offensive threats with Glare so it or its teammates can go to town later on, without a fear of being revenge killed. Both should definitely rise a subrank.
Not gonna say anything about Crabominaids since I don't think I'd be able to fit it on any one of my teams, but I firmly disagree with a ranking for Klinklang. I don't mean any disrespect to Omari or anything, but I don't think I could realistically see myself ever using Klinklang when Magnezone is as good as ever and when I could probably name a million and one better things - including currently-unranked stuff like Snorlax and Salamence - to give a Z-move to. It genuinely just seems like Klinklang doesn't particularly appreciate a great deal of metagame trends and is a bit too dependent on Z-moves to break past stuff and sweep. Normally I wouldn't find this to be a huge deal - after all, regular Gyarados's most common set is a Z-move set and that thing is incredible - but it just seems really outclassed by Magearna (which, btw, I agree should rise back to A+) as a Shift Gear user (it has coverage out the ass which lets it pick and choose its checks), which is further amplified by the fact that Magearna has a half-dozen other sets to run to make it a lot more unpredictable. I don't think Klinklang has a place on the VR, and even if it did I'd realistically seeing it fall back into obscurity within a week anyway.
I also agree with Clefable to S. I've already said a lot about this before, but it offers an astounding amount of role compression and its influence in this tier - extreme to the point where things often have to run moves to lure it in and beat it, and to the point where the support it provides can give other top-tier threats (like Heatran) several options both for coverage/status options and Z-moves - gives it more reason to be ranked among the likes of Lando-T and Heatran.
Finally, I'm going to live by Zygarde to S, and I'm going to die by Zygarde to S. With the offense-filled OLT meta, this thing has been crawling around the ladder and has consistently proven itself to be one of the most versatile, unpredictable, and downright terrifying threats in the metagame. Zygarde is a tried-and-true staple of Hyper Offense, whether it be a standard team, Webs, Screens, or Veil, and can find its way onto other teams just as easily. It's something that, though caught in the Lando crossfire by virtue of its typing, deserves to be as prepared for as it currently is. If the billion and one offensive sets Zygarde can run aren't enough proof of how centralizing Zygarde is in this metagame, perhaps the rise of Glare and Toxic sets can prove how good Zygarde is. Zygarde has nearly no counters; even Curse Mega Scizor (something I've used a lot on my own HO teams) wouldn't appreciate the potential for a Dragon Tail Zygarde, since even Dragon Tail variants have seen usage in OLT to deal with the influx of Reuniclus and CurseZor. All in all, I still think Zygarde is beyond-worthy of rising to S: it's a threat with a decidedly limited movepool, but that movepool is just enough for Zygarde to deal with anything that comes its way.
Adding some newer stuff to this post since some stuff has been posted since I initially wrote this and some of it actually seems kinda interesting:
Keldeo to B or B+: Disagree
I don't really think Keldeo is even remotely at the level of Excadrill, Zard X, and Serperior, let alone at the level of things such as Reuniclus, Mega Sableye, Hoopa-U, and especially Zapdos. A good portion of the tier outpaces it and threatens it with irreparable damage, and the likes of Tangrowth, Tapu Bulu, Mega Lati@s, and Toxapex aren't really doing Keldeo any favors. Considering most of these things are rising or are already very established, top-tier metagame picks, I think Keldeo is pretty fine in B+.
Swellow from UR to C-: Agree
Now this is how you make an Unranked nomination. A great Speed tier, a great ability, and a downright stellar move in STAB Boomburst are all extremely good things Swellow has going for it in this meta. I can realistically see Swellow being C over C-, because its matchup against Hyper Offense - a playstyle that has had a surge of usage in light of OLT - is pretty damn good. It 2HKOs everything but Magearna with Specs Boomburst, and 2HKOs Magearna (which is easily worn down) with Heat Wave and it isn't a complete momentum sap against Chansey to boot. I can conceivably see myself using Swellow to deal with HO teams because it's not dead weight against bulkier archetypes either, so I definitely think it could have a place on the OUVR for the niches you mentioned.
Anyway, that's all I have to say. Apologies for the loooooong post (I ain't trying spoiler formatting this time because I consistently figure out a way to break it), but I feel like I really needed to post here regardless. And did I mention Zygarde should be in S yet?
