Team help

I put this sandstorm team together and tested it with a friend. If anyone wants to watch it, here's the code. It's on ORAS
YTLG-WWWW-WW5C-DQN5

Stoutland
Ability: Sand Rush
Nature: Adamant
Item: Choice Band
Evs: 4 HP/252Atk/252Spd
Moves: Return
Facade
Superpower
Crunch

Excadrill
Ability: Sand Rush
Nature: Adamant
Item: Life Orb
Evs: 4 HP/252Atk/252Spd
Moves: Iron Head
Rock Slide
Drill Run
Swords Dance

Tyranitar
Ability: Sand Stream
Nature: Jolly
Item: Tyranitarite
Evs: 4 HP/252Atk/252Spd
Moves: Rock Slide
Dig
Crunch
Protect

Tyrantrum
Ability: Sand Rush
Nature: Jolly
Item: Leftovers
Evs: 252Atk/4 Def/252Spd
Moves: Stealth Rock
Dragon Claw
Head Smash
Earthquake

Magnezone
Ability: Magnet Pull
Nature: Timid
Item: Choice Specs
Evs: 68 Def/252Atk/188Spd
Moves: Flash Cannon
Thunderbolt
Volt Switch
Hidden Power (FIRE)

Rotom-W
Ability: Levitate
Nature: Calm
Item: Leftovers
Evs: 252 HP/4 SP.Atk/252SP.Def
Moves: Volt Switch
Hydro Pump
Pain Split
Thunder Wave

Any help on improving or just changing a few bits would be much appreciated. This is my first time playing competitively.

Dig is a terrible move in general in competitive play. Not only is it easily telegraphed, it makes the user more vulnerable to Earthquake, especially if said Pokemon is weak to Ground. If you're using Mega Tyranitar, you might as well run Dragon Dance on it (it's an egg move) to make the most out of its power and bulk. Unlike regular Tyranitar, Mega Tyranitar's Speed is actually usable for Dragon Dance sets:
-Dragon Dance
-Stone Edge
-Crunch/Ice Punch
-Superpower/Fire Punch
Nature: Jolly
EVs: 252 Atk/4 Def/252 Spe
Item: Tyranitarite
Ability: Sand Stream

A common mistake when making sand teams is throwing in Ground, Rock, and Steel Pokemon for their sandstorm immunity. This is bad because all three share common weaknesses with each other, which are Water, Fighting, and Ground. Talonflame covers for Tyranitar's weaknesses nicely while also being able to clean up late-game:
-Swords Dance
-Flare Blitz
-Brave Bird/Acrobatics
-Roost
Nature: Jolly
EVs: 252 Atk/4 Def/252 Spe
Item: Sharp Beak/Sky Plate/none
Ability: Gale Wings

or
-Swords Dance
-Brave Bird/Acrobatics
-Will-o-Wisp/Taunt
-Roost
Nature: Adamant
EVs: 248 HP/252 Atk/8 Spe
Item: Leftovers/none
Ability: Gale Wings

Honestly, I'm a bit iffy on Stoutland. While it has Sand Rush, it stacks a Fighting weakness with both Excadrill and Tyranitar. I'm also a bit iffy on Magnezone, as the team can handle Steel Pokemon just fine.

Earthquake outclasses Drill Run on Excadrill in singles. Change Drill Run for Earthquake. Also, changing Swords Dance to Rapid Spin is worth considering, as Talonflame is weak to Stealth Rock and Excadrill is rather strong on its own.

The best Tyrantrum can do is Dragon Dance, a role already taken up by Tyranitar. I wouldn't recommend it as a Stealth Rock setter because of its rather common weaknesses and bad special bulk. Garchomp should be the offensive Stealth Rock setter, as it can still pose a threat even after setting SR:
-Stealth Rock
-Outrage/Dragon Claw
-Earthquake
-Fire Blast/Swords Dance
Nature: Naive/Jolly
EVs: 252 Atk/4 SAtk/252 Spe
Item: Focus Sash/Lum Berry