I'd say either one depending on your liking
Sand
You have that added effect of Sp.def+ and Sand Rush.
A great Pokemon comes along with this as you said: Tyra.
This thing is beast and if anyone tries to disrupt the sand, mega evolve. Excadrill also is good in Sand. It can work without Sand as well. Also SR setters benefit as most of them are Rock/Ground/Steel type. Hurts every Pokemon except those three types. But then again, those types are common.
Good Sand inducer:
Tyranitar @ Tyranitarite/Smooth Rock
EVs: (200 Atk/252 Spd/56 Hp) / (252 Hp/252 Def/4 Sp.def)
Nature: Brave/Adamant/Jolly
-Stealth Rock/Dragon Dance
-Rock Slide/Stone Edge
-Crunch/Pursuit
-Earthquake/Thunder Wave
The ones in italics go together.
Good sand abuser:
Excadrill @ Choice Band/Focus Sash
Nature: Adamant/Jolly (depends on item)
EVs: 252 Atk/252 Spd/4 Hp
-Earthquake
-Rock Slide/Stone Edge
-Iron Head
-Poison Jab/X-Scissor
Good one here.
OR
Tyranitar @ Tyranitarite
EVs: (200 Atk/252 Spd/56 Hp) /
Nature: Jolly
-Stealth Rock/Dragon Dance
-Rock Slide/Stone Edge
-Crunch
-Earthquake
Yep. Can set up and sweep along with the sand benefit.
Hail
Oh, the other benefits. This thing when paired up with Froslass's Snow Cloak, wrecks. Evasion + Blizzard = death. Also, the Walerin strategy you suggested is good. Although you can use Abomasnow and that under Trick Room as well. Try Reuniclus with Overcoat to set up TR so it doesn't get damaged by Hail. This strategy is good and many people won't see it coming half the time which gives you a bunch of misplays from their side which then becomes a one-sided match.
Good Hail inducer:
Abomasnow @ Shoice Band/Abomasite
Nature: Adamant
EVs: 252 Hp/252 Atk/4 Def
Ability: Snow Warning ---> Same thing
-Ice Shard
-Seed Bomb/Wood Hammer
-Ice Punch
-Swords Dance/Rock Slide/Leech Seed
Good Hail abuser:
No TR:
Weavile @ Life Orb
Ability: Pressure
EVs: 252 Ayk/252 Spd/4 Hp
Nature: Jolly
-Low Kick
-Ice Shard
-Ice Punch
-Night Slash
Under TR:
Abomasnow @ Choice Band/Abomasite/Icy Rock
Nature: Adamant
EVs: 252 Hp/252 Atk/4 Def
Ability: Snow Warning ---> Same thing
-Ice Shard
-Seed Bomb/Wood Hammer
-Ice Punch
-Swords Dance/Rock Slide/Leech Seed
Yep, Same thing because it can set up and be BOSS.
Sun
Doesn't damage anything, but you do get MEGA CHARIZARD Y! Wrecks with Flamethrower/Heat Wave. At 159 base Sp.atk, this thing is like a special Tyranitar. Adamant Talonflame outspeeds most things and gets a boosted STAB Flare Blitz which is the best thing on earth. Even better: +1 Flare Blitz from a Mega Charizard X won't even need a damage calc in the Sun. Guaranteed OHKO. Halves water-type moves which also gives some protection from threats such as Swampert and Kingdra. Don't need to set up at all as most fire types are fast enough and some have Drought (fairly common).Even if stopped, fire types function fairly well in most kinds of weather.
Good Sun inducer:
Ninetails @ Heat Rock
Nature: Timid/Modest
EVs: 252 Sp.atk/252 Spd/4 Hp
Ability: Drought
-Solarbeam
-Heat Wave/Flamethrower
-Extrasensory
-Protect
Good Sun abuser:
Charizard @ Charizardite Y
Ability: Blaze ---> Drought
EVs: 252 Sp.atk/252 Spd/4 Hp
Nature: Timid
-Heat Wave/Flamethrower
-Solarbeam
-Air Slash
-Focus Blast/Dragon pulse/Protect
Rain
By far one of the best weather statuses out there. Rain is good. Swift Swim when paired up with rain is better. Swift Swim Swampert with full attack and speed investment with a Jolly nature is best! Kingdra has access to Focus Energy which makes it really good. Also gets the fastest Pokemon: Floatzel with Swift Swim and a Jolly Nature. Floatzel also has good offensive stats at 105/85/115. Can catch the opponents off guard. Blastoise works well in Rain with Mega Launcher and Water Pulse. Non-mega has access to Rain Dish for good recovery. Rain has some good sweepers as well. Politoed is a good Pokemon to set up with Drizzle. Kyogre has Primordial Sea if you don't play by Smogon. The added +50% power on water type moves is pretty good and Kingdra benefits from this really well. Surf is also good in Rain.
Good Rain inducer:
Politoed @ Leftovers/Sitrus Berry/Damp Rock
EVs: 252 Hp/252 Sp.def/4 Sp.atk
Ability: Drizzle
Nature: Calm/Modest
-Scald
-Ice Beam
-Protect
-(any filler move of your choice)
Good Rain Abuser:
Mega:
Swampert @ Swampertite
EVs: 252 Atk/252 Spd/4 Hp
Ability: Torrent ---> Swift Swim
Nature: Jolly
-Protect
-Ice Punch
-Waterfall
-Earthquake
These are just some. I'll edit in more later.
Hope I helped!
-It's a secret!
