Honestly, the Leppa/Harvest set isn't really the scary one. It's the ones that run Psychic Surge or Dazzling/QM that are the scary ones- Psychic Terrain Genesis Supernova KOs basically everything that isn't a seriously bulky resist or max spdef Complete Zygarde/ Eviolite Chansey (or dark types obv), and Genesis followed by Oceanatic Opera kills most of
those- and the one thing that can shrug off being blasted by every Z-move and live (Chansey) can't really do much in return- and because Stoked Sparksurfer is a guaranteed para on top of that, it's entirely possible to just parahax past it. Hell, if you're running Deoxys you could run an
actual Z-crystal Fighting move and threaten an OHKO to even 252/252+ Chansey.
There are only about three BH viable Dark types (Yveltal, Megatar, Megados) and none of them live a Stoked Sparksurfer or Oceanatic Opera. Zygarde can't take Genesis Supernova followed by Oceanatic Opera from Mewtwo without running Assault Vest, but it's type leaves it open to random Ice moves oneshotting it from Deoxys. 252/252+ Giratina takes Genesis pretty well, but then dies to Malicious Moonsault or Soul Stealing 7 Star Strike.
And if you live, then who cares?
There's five more of them standing behind it.
It's as bad or worse than the -ate arguments, or Primal Groudon arguments. One Z-spamming deoxys is fine;
Six is not. With Dazzling and Queenly Majesty existing as well as Psychic Surge and Genesis Supernova, every single one of them will also be immune to priority, and having to run Scarf Skill Link mons just to not lose to a team of six Mewtwo-Y that can sit there spamming Z-moves with no regard to anything does not sit well with me.
Z-Moves. I like them. They can add some nice strategy at both the team building and battling levels by determining who to put them on, what to give up, and when to use that one-shot wonder move. I don't like that the signature ones can be slapped anywhere, not with how strong they appear to be. If anything is done about them, I'd advocate keeping the Z-Crystals legal.
Water Bubble. This thing is like... Huge Power for Water-type moves. Literally. (Huge Power Tackle does about the same damage as unboosted Return, for reference.) It looks like you could just slap it on Scarfed Primal Ogre and start Water Spouting your troubles away. Not to mention the other benefits in Fire-resistance AND burn immunity! Water Bubble Mega-Gyarados? Heck, its basically giving STAB and then some to anything, so you could dump it on anything that could use the Water-coverage, like Zekrom to bop non-Desolate Primaldon and a lot of other things. I worry about this being healthy for the metagame if you're forced to run Water Absorb to not be swept by every random Kyogre.
Trapping. We have even more permanent trapping options that can't be bounced this generation and that has me a little bit concerned. I don't know what to do about this because things like Mean Look is risky because of Magic Bounce while Infestation you can get out of eventually. But Thousand Arrows, Spirit Shackle, and... that anchor move thingy? They hit you and you're stuck unless you happen to be immune, which removes a lot of strategy from play, especially since you won't see it coming until it hits you, like standard. I guess I could keep spamming U-Turn on everything....
Z-moves are cool; Signature Z-moves on everything is
not.
Water Bubble isn't nearly so effective (Though Water Bubble Specs Oceanatic Opera kills very nearly everything coming off pOgre) because pDon are around and
do not care.
I mean trapping is irritating but I've been running six mons with momentum moves since mid x/y so it really doesn't concern me all that much. (It's called Anchor Shot btw)
Since when is running Life Orb any worse than Leppa Berry?
Harvest only works 50% of the time, so unless you add sunny day or have a teammate with Drought, I don't see how that is a bad thing. And at that point you might as well run contrary V-Create instead of a Harvest Leppa which then out damages every Z-Move (if you have a Life Orb or Flame Plate).
If you plan on having Sunny Day or a Drought teammate for a Harvest Leppa user then you could also argue a Rain Dance or Drizzle teammate could help out Thunder under weather:
Switching into a Thunder plus Electric Surge user with Life Orb means 110*1.5=165 * 1.3 = 214.5 base damage, stronger than 10,000,000 Volt Thunderbolt.
If you don't need Rain then just use:
For example Thunderbolt with Electric Terrain alongside Life Orb has 175.5 base power, just above Stoked Sparksurfer. Yes it doesn't paralyze, but you are probably aiming for a KO anyways, and paralysis is nerfed this gen to reduce speed by only 25%.
Yes, at this point you can say 10,000,000 Volt Thunderbolt is stronger, but the point of an Electric Terrain would be to mixed sweep with say Lightning Bolt at over 253 Base Power and Thunderbolt while holding a Life Orb (I.e. Zekrom). Electric Terrain also prevents sleep and can boost any other teammates that pack electric attacks.
I just don't see the trade-off, as even your Higher chance to critical hit is simply:
"10,000,000 Volt Thunderbolt deals damage and has an increased critical hit ratio (1⁄8 instead of 1⁄16)." Or 12.5%
Electric Terrain makes moves stronger than Z moves, benefits your team, and doesn't worry about a 50% chance at hitting more than 1x.
Psystrike with Physic Terrain hits from defense rather than special defense and prevents priority immediately. If the for uses Substitute before you hit with Genesis Supernova you don't even activate the Terrain.
Notably, the issue with Harvest/Leppa that you seem to be ignoring is that while any one of the options that you have proposed hits harder
for that specific type, the Leppa Z-Moves will hit that hard on
every option. And guess what? I'd take the versatility of being able to hit nearly as hard as a Psychic Surge Life Orb Psystrike
and a 50% crit rate move over running Electric Surge LO Thunder in a meta crawling with Primal Groudon and Complete Zygarde.
You also keep mentioning 'Lightning Bolt'. What is this 'Lightning Bolt' (Or, as you called it earlier, 'Lightening Bolt') that you keep referring to? Thunderbolt? Bolt Strike?
Personally, I've been experimenting with Electric Terrain a lot so far, and either way I'd call you an idiot for running LO Electric Surge Zekrom. Role compression is a thing, but Zekrom wants to be
abusing the terrain, not setting it, and it's simply not viable enough in it's own right to work without serious support. Psychic Surge Mewtwo works because Psychic Surge is frankly ridiculous on it and goes well on any team because Mewtwo is and always has been top-tier viable in BH- plus, Psychic is much more of a spammable type than Electric is in a tier where the top two walls and one of the most powerful offensive threats either resist or are immune to it.
Also,
""10,000,000 Volt Thunderbolt deals damage and has an increased critical hit ratio (1⁄8 instead of 1⁄16)." Or 12.5%"
Showdown notes that 10,000,000 Volt Thunderbolt has a 'Very high critical hit ratio' as opposed to, say, Night Slash's 'high critical hit ratio'. Given how often it crits
me I'm willing to bet that the crit ratio is anywhere from 33% to 50%.
Also, anyone Substituting in front of a Ytwo that hasn't yet revealed Harvest is incredibly foolish, due to how common Dazzling/QM are. Of course, this expects that the person is running Prankster; Anything faster should be attacking anyway, and if Harvest has been revealed then Genesis Supernova has probably already established Psychic Terrain.