But since it's choice banded, it wouldn't matter if it got blocked by a ghost because Return is too. I use it to take advantage of Dodrio's ability. I think I will keep thrash. I will do the Musharna change. However, the problem is both Torkoal and Armaldo don't fit too well with the synergy. I will try both and keep you updated.
Also, I don't really have a special wall after the change to Musharna, so I have to find some type of EV spread that works.
UPDATE: I lost nearly every single game with the changes :/
Keep Armaldo. It's the rest of the team that needs work.
Another Pokémon to consider is Sawk, who can beat the Rocks and Steels that plague Dodrio:
-Close Combat
-Ice Punch
-Stone Edge
-Earthquake/Reversal/Toxic
Nature: Adamant/Jolly
EVs: 4 HP/252 Atk/252 Spe
Item: Choice Band/Choice Scarf
Ability: Mold Breaker/Sturdy
Golurk can stay, thanks to its ability to absorb Electric moves aimed at Dodrio.
Musharna also stays because it also beats Rock Pokémon; it can also use Heal Bell.
I think Ludicolo deserves a mention for a special wall:
-Substitute
-Leech Seed
-Toxic/Scald
-Ice Beam
Nature: Calm
EVs: 252 HP/4 Def/252 SDef
Item: Leftovers
Ability: Rain Dish
An additional hazard setter like Garbodor might not be a bad idea:
-Spikes
-Gunk Shot
-Drain Punch/Toxic Spikes
-Clear Smog/Giga Drain
Nature: Impish
EVs: 252 HP/240 Def/16 Spe
Item: Black Sludge
Ability: Aftermath
or
-Spikes
-Gunk Shot
-Drain Punch/Toxic Spikes
-Seed Bomb
Nature: Adamant/Jolly
EVs: 4 HP/252 Atk/252 Spe
Item: Air Balloon/Black Sludge
Ability: Aftermath
Edit: here's yet another reason why you shouldn't use Thrash. If Dodrio uses it, then it'll be forced to stay in battle, which is very problematic if a Steel or Rock Pokémon, which can shrug off Thrash, switches in.