Okay, I haven't even attempted to make a "serious" team yet, since the meta is a madhouse and is probably going to take another month or two to really settle down between bans, people moving past new toy syndrome to settle on what actually works, and whatever decision is made with Tera. I've been exclusively laddering on my meme account, mostly testing out second tier mons and off-meta sets and sticking in the high 1400s across a bunch of styles. So, here are a bunch of thoughts from a truly mediocre player:
Gholdengo/Glimmora cores rarely seem as effective in practice as they do on paper. Glimmora just isn't that great at setting up hazards beyond TSpikes, and even then, the activation order with toxic debris rapid spin really hurts it. I honestly think Rocky Helmet Endure Glimmora is a decent set to create more opportunities later in the match to get up multiple layers of Tspikes while possibly messing with Rapid Spinners. But, really, that's mostly a good reminder that Garchomp might be the best hazard setter in the tier. Vastly bulkier, and that helmet+rough skin chip adds up quick and functionally blocks spins from weakened `mons. Clodsire and even Gastrodon are pretty fire, too, for more defensively minded teams. Gastro getting spikes and rocks is legit huge.
As for Gholdengo in particular, its defog immunity is really just icing on the cake, since using it to protect hazards just invites it to die to knock -> EQ from either new Donphan form. The overall status immunity, and the fact that it includes things like taunt, disable, and leech seed, is huge. I get the appeal of Scarf sets, but bulky Air Balloon has my heart when I stoop to using it.
Iron Moth is definitely best run with Agility but then it has severe 4MSS. It also wishes it could run Boots and LO at the same time, but if it gets lucky with a Fiery Dance boost or two, watch out.
Solid post, big ups. I'm only gonna comment on the quoted sections (Chomp hazard lead, Gholdengo, & Agility Iron Moth), as they're the only ones I feel as though I have enough experience with to provide anything of merit.
I've been using a lot of lead Garchomp instead of Glimmora on the typical Goldie+Spikes HO, with
this set. The spread is simply Atk investment to OHKO 4Def Gholdengo, rest in HP, 4Def, and max Spe for obvious reasons. The advantages over Glimmora are more than one might initially expect, as not only does the bulk go a long way in ensuring you get multiple Spikes up, it also offers some nice defensive utility for HO, whilst allowing Chomp in many match-ups to set hazards repeatedly, either to reset them
should the opponent play well enough to get them off, or to get up an addition Spike later on in the match.
Futhermore, Dragon Tail on a dual Hazards lead, especially one like Garchomp, is an incredible move. Though the obvious meme of setting your own Rocks AND Spikes AND phazing (shout out the Ting) is tremendously strong, it also proves itself invaluable in the current setup-ho & stall festered metagame - providing recourse against the many offensive threats that frail teams (such as your own) fear, & invaluable chip against the other extremely defensive types. The great attacks don't stop there, though. Earthquake in this meta, especially offensively-inclined Garchomp's Earthquake, is very strong, due to the sparsity of top-tier Ground immunities/resistancies. Even the sturdiest, Corviknight, you can always keep rocks up vs as a minimum, and then phase them later or get an addition Spike.
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Gholdengo, in my opinion, is overcentralising, and potentially "broken", in the traditional sense of "overwhelmingly strong in comparison to its peers". In defence of this claim, I will examine three things that I believe illustrate this,
1. The general structure of the meta-suitable builds.
2. The lack of universal, reliable, viable, means of handling Gholdengo, that do not destabalise the metagame further by compromising other crucial matchups.
3. It's usage rate, which is currently ranking it at the #1 spot of OU.
(1): We see a high degree of homogeneity within the current metagame, by this I mean the presence of either hazards/screens HO paired with Gholdengo, stall attempting to counter this (and largely failing, thanks to Gholdengo), or some mid-point bulky offence with their own Spikes, also often featuring Gholdengo
(2): Gholdengo, ability notwithstanding, is an incredibly strong Pokemon. I won't go over the stuff everyone knows, such as great typing, stabs, power etc., but I will say that its main two sets, Scarf+Trick+Plot/Focus Blast, Balloon+Plot+Recover/Focus Blast, are effectively uncounterable without an overcommital of resources for the matchup, or by using more generally unviable techs. The former set makes it excellent vs offensive threats & defensive ones, the latter performing more reliably as a spin blocker & crushing defensive structures.
(3) Usage rate alone, does not indicate whether or not a Pokemon or element centralises the meta to an unreasonable or even unhealthy degree. Historical examples of high-usage, non-problematic are GSC Snorlax, or any recent meta with regards to Landorus-T. I believe the case of Gholdengo is different, when the (1) & (2) are taken into account. Gholdengo, in my eyes, sets the stage, pace, & general structure of viable builds in the metagame, in an unhealthy manner. Gholdengo is the lynchpin (as is Tera, though to a lesser extent) of pretty much all of the problematic builds we see in the meta, as they simply cannot be anywhere near as functional without Gholdengo.
Not to say it should be priority #1, Gholdengo, in the sake of seeking a competitive, stable, & balanced meta is an influence I believe must be excised from the OU metagame, with as much haste as possible.
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Iron Moth is a really interesting & fun mon, that I consider to be quite strong. I think you're correct in asserting that 3 attacks Agility is its best set, though I would suggest that it is best utilised with
this set, on a strict HO team. Life Orb is a means of hampering yourself, as Booster Energy does the same thing without the loss of bulk, and Boots forgoes the heavy offensive pressure that Proto-boosted Iron Moth applies. Grass is currently standard as a Tera type for Iron Moth, though I think there is significant justification to use Psychic on many (if not most) teams, due to the omnipresence of Clodsire - depends on the team, really. God help those facing a +1 SpA, +2 Spe, Proto-boosted Iron Moth.
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Here is a team for anyone reading to use & get a sense of the things I covered in this post. DD Acro Roaring Moon is better than Iron Valiant in this slot, so use that if you prefer to. Have fun.
the biggest meme of them all, I hate this meme, but Gale Wings defog + fire stab is good, is literally the third best deffoger
