Multiscale D-nite without Roost is retarded IMO.
Your avatar isn't Magikarp anymore.
Smogon's back up again, which is nice. I'm going to be setting up a team of Pokemon made specifically for beating up my friends after I'm done with White 2. I started working on it, and half of the team ended up being Steel types because I'm an idiot. It might be a compilation of my best Pokemon from other parties like Excadril and Heracross with some new Pokemon thrown in. I don't know yet.
It's good to hear that Magikarp's returning, and all of a sudden everyone's avatar has a sword in it.
Espmaster and I put together a 5th gen. doubles team shared between us.
252 HP/252 Atk/252 Spe
212 SpA/40 HP/252 SpD
252 HP/4 Def/232 Spe/20 SpA
146 Atk/110 SpA/252 Spd
252 SpA/40 HP/212 Spe
-Ice Beam (Rapid Spin)
252 HP/136 SpD/76 Def/40 Spd
The Pokemon are listed in the order they're sent out into battle. We start off with Slaking and Eelektross, where Eelektross uses Gastro Acid on Slaking. The Focus Sash is there to ensure Slaking loses its Truant ability. Eelektross has Levitate so that Slaking can spam Earthquakes without much harm. When Eelektross does faint, Espeon is sent out to put up a Reflect/Light Screen, and to maul any Fighting types after Slaking. When Slaking faints, Salamence, the even deadlier force is sent out. Espeon is called back/faints for Starmie, while Umbreon is occasionally sent out to Wish heal Salamence.
Believe I've already complained t' one of ya that EQ spamming in Doubles ain't viable without STAB. Give Slaking a Choice Band, or expect lackluster damage output.
Focus Sash guarantees a move much less than it does than in Singles. If a good Doubles team wants to prevent Gastro Acid, they'l most certainly manage. Be it Fake Out, Sleep, targeting Eelektross twice, or Taunt. 'Course, that's a moot point since it's doubtful you'll see a player good enough t' counter the ol' "remove Truant" strategy/with a team capable of doin' so in one turn.
Salamence's best quality for Doubles is Intimidate and it's Flying-type... so it's not really somethin' you want to singularly rely on for damage output. 'Specially since Draco Meteor forces a switch and it's EVs aren't maxed out in either attack stat. It's great for an offensive duo, but can't stand alone easily like with Truant-less Slaking.
Lastly, I understand you're goin' for the Eeveelution dynamic here, but Umbreon's terrible for Doubles lol. That set especially. Wasting time to Wishpass is... well, a waste of time. Foul Play deals unreliable damage as well.
As for Slaking, Choice Band wouldn't work with the strategy well, so we'd have to change it up quite a bit. Perhaps just a Life Orb? I can imagine max attack Slaking's EQ x1.3 doing a bit more than "lackluster damage." But maybe that's just me.
On that note, should I put Protect over Grass Knot on Espeon? I don't think Espeon likes to take Earthquake much, STAB or not.
Wish is a hindrance rather than an aid in Doubles, hence my rejecting of Umbreon.
Earthquake only has 75 BP when hittin' two or more Pokes. Even with a Life Orb, you're not gonna OHKO anythin' besides things weak to EQ/glass cannons like an Espeon. If a hit ain't an OHKO, it's a 2HKO. And one-shotting targets 'fore they move is incredibly valuable in Doubles. When I say lackluster damage, I mean you're missin' those OHKOs and therefore Slaking's gonna die soon. Eelektross isn't very useful outside'a Acid Spray-ing Truant away since it's very slow and can't pick up KOs Slaking sets up for, meanin' a smart foe will target Slaking, off it, and ignore the minimal damage Eelektross does (if it's not hitting super-effective). This is the reason why I don't like usin' Regigigas or Slaking in Double battles. Removing their ability or not, they're still novelties due to the issues they bring.
Against a good trainer, if you have a Poke out that can't automatically dodge EQ, and it's obvious you want t' spam EQ, they know you'll either switch or Protect. As such they'l focus on the EQing Poke. Protect is a great move on any Poke in Doubles, but ProtectQuake/Surf/Plume/whatever is very much overrated when the strategy is in any way obvious. That, and they can always counter Protect and/or switch to EQ-immune or resisting Pokes. Point bein', Espeon could certainly use Protect, but it's better off settin' up Screens as quickly as possible and then dyin' while throwin' out a Psychic or two. Or switchin' to 'Mence to better continue EQ spam so Espeon can suicidescreen one more time later.
By the way, the Latis are utterly superior at Screening. Both Levitate over EQ, have potent Dragon STAB, better movepools, and better typing. Latias is bulky, whereas Latios maximizes damage output. Light Screen to partially protect Slaking from Latios' Surf spam, combined with EQ spam will get quite a few 2HKOs. Not that ya care I'm sure, I'd sooner use a Stall team than you'd replace Espeon for anythin'.
Oh, and give Slaking Return. Pokes die quickly in Doubles, so paralysis is rarely of consequence unless you're intentionally spreadin' it en masse via reliable status moves (T-wave)/Discharge spam.