Emerald battle frontier team

I have a Battle Frontier team on Emerald, but I need some help with it. Here are my current Battle Frontier Pokémon

Starmie @ Leftovers
Natural Cure
- Surf
- Ice Beam
- Thunderbolt
- Psychic

Your typical boltbeaming Starmie. I am thinking about replacing Psychic with Recover or Thunder Wave, but I am not sure.

Heracross @ Persim Berry
Swarm
- Brick Break
- Earthquake
- Megahorn
- Rock Slide

I am thinking about replacing one of the moves with Swords Dance, but I can't decide which one... Also maybe I should replace the item, I have a sizeable amount of battle points to buy one.

Latios @ ???
Levitate
- Psychic
- Recover
- ???
- ???

I just caught this, and the moveset is not complete yet. Also suggest an item, but keep in mind I can't get the Soul Dew because I can't get to Southern Island. I kind of want Toxic on it so (particually Greta's) Shedinja doesn't wall me.

Ludicolo @ Miracle Seed
Swift Swim
- Surf
- Giga Drain
- Ice Beam
- Fire Punch

I don't use this much, and I have sort of replaced it with Latios, but I may still use it. Item help for it would be appreciated.