Is this a good pokemon team? for pokemon diamond!?

Here is my Pokémon team, all tips would be welcome (: – Shuckle (100) @ Lax Incense:; Toxic, earthquake, Double Team, Rest – Darkrai (100) @ (I article here), Nightmare, Dream Eater, Dark Pulse, Dark Void – Gyarados (100) @ Life Orb? (Or other),, Dragon Dance Ice Fang, earthquake, Waterfall – Salamence (100) @ (Articles ?):;; Draco Meteor, Flame thrower, Fly, Crunch – Arceus (100) @ Draco Plate:; and ending with Blizzard Future Sight, die Song – Heatran (100) @ (Art?), Earth Power Stone Edge, Magma Storm, Iron Head, so that in principle I need some advice on the various elements and movements, or? Thank you (: @ Drew Peacock, what factors do you think I should make my pokemon?

Yes, It is, however, make a strong pokemon to suck the other

How to get Draco Plate