This is a good team props on using Aero. I'm pretty familiar with sand so let me give you a few suggestions.
Spikes Rosie is a staple on sand balance teams, use it. Spikes help wear down common Stoutland switchins like Registeel, Rhypherior, Hitmontop (who will be pressured to come in and spin), and with multiple layers Stout can even 2hko Slowbro.
Roserade @ Leftovers
Trait: Natural Cure
EVs: 252 HP / 248 SpDef / 8 Speed (prolly oughta creep more tbh)
- Giga Drain
- Sludge Bomb
Now you need a spinblocker for all those hazards, so try replacing Alakazam (he seems like you just tacked him on) with a stallbreaker Missy. Missy can even lure in Registeel and deal it a crippling burn =D.
Mismagius @ Leftovers
EVs: 252 HP / 4 Def / 252 Spd
- Shadow Ball
- Pain Split
My next suggestion is to try CB Stoutland. With spikes support he is a monster and CB lets him bulldoze through the lack of coverage. Makes an insane revenge killer and late game cleaner. Btw Wild Charge sucks. Pursuit is a lot more valuable imo to trap ghosts that normally impede his sweep. If you wanna keep LO (it's definitely easier to use prediction wise), still consider changing out Wild Charge.
Stoutland @ Choice Band
Trait: Sand Rush
EVs: 4 HP / 252 Atk / 252 Spd
The only other change I recommend is Roar over Stone Edge on Hippo. He's an excellent phazer in UU being able to force out the majority of physical attackers and in conjunction with spikes support, he can really wreak havoc. Racking up residual by shuffling through the opponenet's team also helps weaken things into Stoutland's KO range by lategame.
GL dude. I definitely can't post my sand team now because they all look so similar XD
who is this character