My Pokemon Diamond Team. (Rate in percentage)

Here's my Diversity team:

Jolteon Timid @Magnet
Trait: Volt Absorb
-Thunderbolt
-Shadow Ball
-Charge Beam
-Thunder Wave

Lucario Gentle @Black Belt
Trait: Steadfast
-Close Combat
-Aura Sphere
-Flash Cannon
-Calm Mind

Charizard Relaxed @Focus Sash
Trait: Blaze
-Heat Wave
-Flamethrower
-Dragon Pulse
-Air Slash

Slowking Quite @Mystic Water
Trait: Own Tempo
-Psychic
-Water Pulse
-Nasty Plot
-Trick Room

Garchomp Quite @Lansat Berry
Trait: Sand Veil
-Earthquake
-Stone Edge
-Dragon Claw
-Swords Dance

Any suggestions about the sixth pokemon?

Sixth pokemon:

Gyarados (nature you prefer) @Leftovers
Trait: Intimidate
EVs: Defense
-Earthquake
-Hydro Pump
-Ice Fang
-Dragon Dance

or

Milotic (nature you want) @Leftovers
Trait: Marvel Scale
EVs: Attack
-Hydro Pump
-Ice Beam
-Surf
-Recover

Your Jolteon's good, Timid nature makes him fast and he's already a fast pokemon. I would take Charge Beam out for Hyper Beam or Iron Tail.

Teach your Lucario Earthquake and Psychic and take out Flash Cannon and Calm Mind.

Teach your Charizard Iron Tail or Brick Break to combat his Rock type weakness. Teach him Dig or Earthquake to combat his Electric weakness.

Definitely teach your Slowking Flamethrower, because he's weak against Grass and Bug types. Teach him Earthquake or Dig and Shadow Ball also.

Ouch, that's a bad nature for your Garchomp, because it raises his Sp.Atk and lowers his Speed and Garchomp is a powerful physical sweeper, which means he has high attack and speed base values. I suggest breeding for a different Garchomp like I did. Breed one with an Adamant nature. He'll be extremely stronger. Other than that, his moves are just right for a Garchomp.

I think you should take a Bug pokemon like Heracross in your team. Your team's weaknesses are Electric and Ground. I rate your team a 74.51% since you don't have a sixth pokemon yet, but if you do all the changes it will probably be a 89.92%.

Sixth pokemon:
Heracross Adamant/Lonely/Naughty
Trait: Swarm
Evs: Attack and Speed (Physical Sweeper)
-Earthquake/Dig
-Megahorn/Giga Impact
-Close Combat/Aerial Ace/Swords Dance
-Rock Slide/Stone Edge

Thanks Caleb. I'll try my best on changing Garchomp's Nature.

...how do u change their nature?

Dialga, keep Calm Mind, dont teach Lucario Earthquake. Trust me, his sp. atk. is good, not atk. and for ur last pokemon, i suggest a grass type, maybe Roserade. if u were allowed Legendaries, I'd suggest Celebi, so u could also have a psychic type.

For charizard, take away Heat Wave, there's no need for it, and teach it Blast Burn. that way u got a fire type move that u can use regularly, and one for wen ur about to die, or wen ur in a pickle.

I dont no much about the other pokemon, just those 2.

Yes,breed and get a Jolly or Adamant Garchomp.If you get a Jolly EV train in Speed and Attack.

My pokemon diamond team please rate:D
Blastoise (hasty)
Trait: Torrent
-ice beam
-flash cannon
-hydro cannon
-dig

Sceptile (Careful)
-dragon claw
-iron tail
-leaf blade
-X-Scissor

Blaziken (Hasty)
-Earthquake
-Blaze Kick
-Giga Impact
-Sky Uppercut

Walrien (Gentle)
-ice beam
-crunch
-earthquake
-water pulse

Salamence (Mild)
-Draco Meteor or Dragon Claw?
-Crunch
-Earthquake
-Flamethrower

Gengar (lax)
-Hypnosis
-Dream Eater
-Dark pulse
-Poison Jab

Any Suggestions
What items?
What moves?
New pokemon?

Well Salamencetamer25, you could of posted a new Topic about your pokemon, not in someone elses Topic.

lol

Can you at least rate it please?