Ferrothorn: Change Brave nature to Adamant. The EVs is wrong... go 156 Def / 252 SpDef / 100 Atk. The EVs should always be divisible to 4.
Gliscor: All OK. But your team is really weak to Ice-types so I prefer change it to Tentacruel.
Tentacruel @ Black Sludge
Ability: Liquid Ooze
Nature: Timid (+Spd -Atk)
EVs: 4 Def / 252 SpAtk / 252 Spd
-Scald
-Hex
-Rapid Spin
-Ice Beam
or
Tentacruel @ Black Sludge
Ability: Liquid Ooze
Nature: Bold (+Def -Atk)
EVs: 252 Def / 252 SpAtk / 4 Spd
-Toxic Spikes
-Venoshock
-Hidden Power(Ground)
-Rapid Spin
Dragonite: Go with Adamant too.
Latios: Soul Dew is banned. Go with Life Orb. And I prefer Timid Nature (+Spd -Atk) to go sweeping.
Deoxys-D: Same as Ferrothorn. I think you wanted 116 Def / 116 SpDef / 200 HP / 76 Spd with Jolly Nature(+Spd -SpAtk). But I prefer go with 20 HP / 232 Def / 252 SpDef with Bold Nature(+Def -Atk). Change Seismic Toss to Night Shade because Deoxys-D can't learn Seismic Toss.
Volcarona: Change Acrobatics for Giga Drain.
