Mono-Ground Sand Team, What Changes Should I make?

Question

1) Hippowdon @ Leftovers
Ability: Sand Stream
EVs: 248 HP / 252 Def / 8 SpD
Impish Nature
- Earthquake
- Slack Off
- Stealth Rock
- Roar

This is my physical tank. The reason why I went for Hippowdon instead of other Ground-Type physical tanks such as Gliscor and M.Steelix is because of his ability Sand Stream. I've focused this team around abilities such as Sand Force and Sand Rush, which you will notice later on.
The set is self-explanatory.

2)Garchomp @ Garchompite
Ability: Sand Veil
EVs: 252 Atk / 4 SpD / 252 Spe
Jolly Nature
- Earthquake
- Fire Fang
- Outrage
- Swords Dance

I decided to use M.Garchomp because of Sand Veil(Normal) and Sand Force(Mega). The 4x weakness to Ice is a downsider, especially since this is a Mono-Ground team, but I needed the speed and attack since this team is extremely slow without Sand up to activate Sand Rush.
I could've given him a Choice Scarf but the Swords Dance allows him to create mini-sweeps. Outrage can be bad against Fairy-Type Pokemon but Dragon Claw is useless due to not doing enough damage. Rock Slide instead of Fire Fang would also be good with the boost from Sand Force, allowing Garchomp to no longer get fully countered by Air Ballon Heatran, but I'd rather have the Coverage to stop mons such as Ferrothorn and Scizor.

3)Gastrodon @ Leftovers
Ability: Storm Drain
EVs: 252 HP / 4 Def / 252 SpD
Calm Nature
IVs: 0 Atk
- Scald
- Toxic
- Recover
- Ice Beam

Gastrodon is the closest ground-type mon to a Sp.Defensive Wall, it being the main reason I'm using him. The other reason is for not being weak to ice and water. Yes, the 4x grass weakness is a problem but, depending on the pokemon and set, Gastrodon can live an Energy Ball/Giga Drain withot rocks/spikes damage.
The set is pretty basic exccept that I decided to use Ice Beam instead of Earth Power for the coverage. Sand Force with Earth Power instead of Ice Beam could've been an option but I needed the water immunity.

4)Excadrill @ Focus Sash
Ability: Sand Rush
EVs: 252 Atk / 4 SpD / 252 Spe
Adamant Nature
- Earthquake
- Iron Head
- Rock Slide
- Sandstorm

Excadrill is preety basic, not much to say about him.
The idea with this set is to set up the Sandstorm, being able to resist at least 1 attack with focus sash. And then try to make a mini-sweep, with Sand Rush. Rapid Spin was an option but I already chose another pokemon to give Rapid Spin, plus he's the only pokemon in this team with Steel and Rock type coverage. I gave him Adamant because he won't really need the speed bonus from Jolly, Sand Rush is enough to outspeed most choice scarfers. This sets main weakness are priority moves.

5)Nidoking @ Life Orb
Ability: Sheer Force
EVs: 4 Def / 252 SpA / 252 Spe
Timid Nature
IVs: 0 Atk
- Ice Beam
- Earth Power
- Sludge Wave
- Flamethrower

Nidoking main reason of existence is for the Special coverage, since ground-type pokemon are often physical. Yes, Landorus could've been an option as well but I decided to use Nidoking instead for more coverage.
The set is self-explanatory.

6)Sandslash @ Focus Sash
Ability: Sand Rush
EVs: 252 Atk / 4 Def / 252 Spe
Jolly Nature
- Rapid Spin
- Sandstorm
- Earthquake
- Knock Off

Is Sandslash an odd choice? Yes. Is Landorus-T probaly better? Yes. Does that mean Sandslash is useless? No. Yes, using Sandslash is weird but I think he's a good choice for this team.
The set is pretty standard with Rapid Spin, Knock Off and Earthquake for stab. It's set is similar with Excadrill's, getting the Sandstorm up and then trying to be usefull. Yes, it's weird that I'm using Sandslash but I think he's a good mon in this team comp.

That's about it, you can go ahead an suggest me if I should switch out mons for other mons, if I should change the movesets, etc. I'd like to see your oppinion!
P.S. I have no idea if any of the images will work.