first off, natures and EVs and IVs should concern you if you're battling other people since each little thing can make all the difference. the natures really help in creating a pokemon that will fulfill your request.
Jolteon
Item: Don't Know
Thunder Wave
Baton Pass
Agility
Charge Beam
Baton passing agility and\or special attack increase.. that's my impression of this Jolteon. Thunderwave is decent due to paralizing a pokemon and charge beam might increase your special attack.. a stabbed charge beam is not that bad of an idea... especially since you'll be embracing the baton passing concept. You can either give him a stat increasing berry or a berry to reduce the damage of a strong ground move.
Alakazam
Item: Don't Know
Psychic
Recover
Focus Blast
Charge Beam
You might not be able to get a chance to use Recover, FYI, since Alakazam is a delicate pokemon, so you might want to use a move like Energy Ball to add more supereffective Coverage, or even teach him calm mind so that if you can sneak it in, you'll make his sp attack a lot more dangerous... which I can tell you'll be trying to do with Charge Beam. I'd personally prefer using Thunderbolt because of its chance of paralysis while being a harder hitting move. As a hold item, a choice scarf or choice specs would make him a nice force to reckon with.
Steelix
Item: Don't Know
Earthquake
Stone Edge
Explosion/Stealth Rock
Gyro Ball
Earthquake\Stone Edge is a decent move combination since it has a lot of coverage, Gyro ball hits hard since Steelix is a weak pokemon, but you might find yourself wanting to get rid of Gyro Ball OR Stone Edge to embrace Explosion and Stealth Rock. Just keep in mind, also, that despite Steelix's massive physical defense, he has weaknesses that are found in common moves like Brick Break, Flamethrower, Earthquake, Surf.... a stab special attack will take him down in one hit. In terms of a held item, leftovers is a decent way to go on him.
Skarmory
Item: Don't Know
Toxic
Roar
Spikes
Aerial Ace
You might want to try a different Skarmory. The standard Skarm comes with:
Spikes/ Stealth Rock
Roar/ Whirlwind
Drill Peck/ Steel Wing
Roost/ Rest
You want to embrace Skarmory's high defenses, so a recovering move would really come in handy. Rest is probably the better way to go since it gets rid of status afflictions and FULLY recovers HP. Spikes versus Stealth Rocks, each has their better moments, but Stealth Rock guarantees damage. Roar vs. Whirlwind... I'm more partial to whirlwind since it has more coverage (affects soundproof pokes).. and Drill Peck is the best stab move of choice while Steel Wing has a chance of boosting your defense... Toxic WOULD come in handy IF you were able to stall long( that means with healing) enough to embrace its brutal effects... A good item on Skarms are Chesto\Leftovers depending on whether you'll be using Roost or Rest
Miltank
Item: Don't Know
Heal Bell
Milk Drink
Curse
Body Slam
This is a decent moveset since it also beefs up the miltank, so for an item, leftovers might come in handy, since it will allow this poke to last longer in battle, at least long enough to set up Curse... but Curse would become useless if you're facing a ghost pokemon since you won't be able to strike it.
Dusknoir
Item: Don't Know
Rest
Earthquake
Payback
Will-O-Wisp
This moveset is OK... Payback works well since Dusknoir is typically the slower guy and earthquake covers Paybacks resistances.. but a Skarmory can take it. Will-o-Wisp comes in handy since it physically weakens a pokemon, but be prepared to watch it miss, come up with something that can cover that. and Rest... he's got such low HP that Painsplit would work better.... if you're going to rock w\ Rest, use a Chesto Berry or give him Leftovers... but FYI.. Rest might not work that well. I'm assuming that you're going to use Dusknoir to counter physical moves since you have Will-o-Wisp to weaken them.
just keep in mind that a blaziken or Infernape can counter your team... the most common weakness is Earthquake....
This does seem like a decent team, but if you knew what natures and IVs+EVs you were going to utilize, you could make it better.
