Trying to beat E4 in diamond and I haven't played pokemon really in depth since fire red and leaf green.
Right now my party is
Torterra
Lvl 53 overgrow
Crunch
Gigadrain
Razor leaf
Earthquake

Dialga
Lvl 52 Pressure
Metal claw
Aerial ace
Ancient power
Roar of time

Bronzong
Lvl 48 ?
Charge beam
Psychic
Gyro ball
Flash cannon

Steelix
Lvl 49 sturdy
Crunch
Dragonbreath
Stealth rock
Iron tail

Noctowl
Lvl 45 ?
Air blade
Fly
Zen headbutt
Steel wing

Weavile
Lvl 46
Night slash
Slash
Icy wind
Faint attack

Should I train up or switch in a garchomp, abomasnow, skuntank, raichu, floatzel. The heracross keeps messing me up..