So yeah, this is my new new team. I've been working on it for about a week, and it got me to #1000 on pokemon online's DW ladder, which I'm proud of. All I need now are some finishing touches before I make it for B/W wifi.
Ferrothorn @ Rocky Helmet
Iron Barbs
252 HP, 128 Def, 128 Sp Def
Careful (-Sp atk, + Sp def)
Protect
Leech Seed
Power Whip
Thunder Wave
This ferrothorn doesn't carry stealth rocks, since I normally switch in to espeon first turn to magic bounce the opponent's rocks back at them. Ferrothorn acts as a good lure for fire types too, meaning I can switch in Arcanine to get a flash fire boost. Since he lacks a reliable healing move, Leech Seed+Protect lets him recover some of his health each turn, while also wearing down my opponent. Ferrothorn's job is to act as a lure for fire types and stealth rocks, and cripple sweepers with leech seed+thunder wave+protect. Rocky Helmet+Iron Barbs also leaves a nice dent in my opponent.
Suicune @ Leftovers
Water Absorb
252 HP, 128 Def, 128 Sp Def
Bold (-Atk, +Def)
Calm Mind
Surf
Protect
Toxic
After looking at my team, I realised that Suicune had the potential to be a reliable wall all along. With Calm Mind, he can boost his Special Attack and Special Defense, so a Bold nature helps by boosing his physical defense. Toxic lets me cripple other walls or pokemon who try to set up on me, and Surf is a reasonably powerful move after a Calm Mind or two.
Salamence @ Lum Berry
Moxie
252 Attack, 252 Speed, 4 Sp Atk
Naive (-Sp Def, +Speed)
Dragon Dance
Dragon Claw
Earthquake
Fire Blast
Salamence is the core of my team. After one dragon dance, he hits 492 speed, outspeeding virtually the entire metagame. After that, he just hits harder and harder, thanks to moxie. Earthquake is for steel types, who are the only pokemon to resist Dragon Claw, and Fire Blast takes care of Skarmory and Ferrothorn, who would otherwise wall Salamence to the end of days. The Lum Berry also lets me get an extra turn against pokemon who would otherwise cripple me with thunder wave or will-o-wisp.
Darmanitan @ Life Orb
Sheer Force
252 Attack, 252 Speed, 4 HP.
Jolly (-Sp Atk, +Speed)
Flare Blitz
Rock Slide
Earthquake
Superpower
I changed Arcanine to Darmanitan, which seems a bit of a shame to me (I really like Arcanine). A slight variant on what Browners suggested, I changed the nature to Jolly, since Life Orb Sheer Force Flare Blitz is going to hurt anyway, and I feel Darmanitan needs a little bit of a speed boost to help it sweep some of the faster pokemon that would otherwise outrun it and kill it off.
Porygon-Z @ Choice Scarf
Adaptability
252 Attack, 252 Speed, 4 HP
Modest (-Attack, +Sp Atk)
Hidden Power (Fighting)
Dark Pulse
Tri Attack
Trick
I'm often wary about using Choice Scarf, since I don't think it gives pokemon an amazing boost. However, Porygon-Z looks like one pokemon that can really use it. Having the scarf allows Porygon-Z to run a Modest nature, boosting his special attack stat to a monumental 404. With that kind of power, and Adaptability kicking in, Tri Attack is going to really hurt anything that doesn't resist it. Dark pulse takes care of Ghost types who resist my STAB, and HP Fighting deals with Steel types. Even better, I can trick my opponents into a set-up move and still have enough power to hit hard.
Espeon @ Choice Specs
Magic Mirror
252 Sp Atk, 252 Speed, 4 HP.
Timid (-Attack, +Speed)
Psyshock
Hidden Power (Fighting)
Grass Knot
Shadow Ball
Not quite so effective as my Choice Specs Trick Espeon back in 4th Gen, but at least now it has an awesome ability. Magic Mirror allows my Espeon to switch in on stealth rocks, spore, and thunder wave and bounce them right back at the opponent. Psyshock has less power than Psychic, but allows me to take out special walls with low physical defense like Chansey. Hidden Power replaces Signal Beam as a counter to dark types, and also hurts Steel types too, which is an added bonus. Grass Knot deals with bulky waters like Quagsire and Swampert, whereas Shadow Ball works well against slower Ghost Types like Dusclops and damages other Psychic types.
Meet The Team






I'll talk through why I chose each pokemon one at a time.

Ferrothorn @ Rocky Helmet
Iron Barbs
252 HP, 128 Def, 128 Sp Def
Careful (-Sp atk, + Sp def)
Protect
Leech Seed
Power Whip
Thunder Wave
This ferrothorn doesn't carry stealth rocks, since I normally switch in to espeon first turn to magic bounce the opponent's rocks back at them. Ferrothorn acts as a good lure for fire types too, meaning I can switch in Arcanine to get a flash fire boost. Since he lacks a reliable healing move, Leech Seed+Protect lets him recover some of his health each turn, while also wearing down my opponent. Ferrothorn's job is to act as a lure for fire types and stealth rocks, and cripple sweepers with leech seed+thunder wave+protect. Rocky Helmet+Iron Barbs also leaves a nice dent in my opponent.

Suicune @ Leftovers
Water Absorb
252 HP, 128 Def, 128 Sp Def
Bold (-Atk, +Def)
Calm Mind
Surf
Protect
Toxic
After looking at my team, I realised that Suicune had the potential to be a reliable wall all along. With Calm Mind, he can boost his Special Attack and Special Defense, so a Bold nature helps by boosing his physical defense. Toxic lets me cripple other walls or pokemon who try to set up on me, and Surf is a reasonably powerful move after a Calm Mind or two.

Salamence @ Lum Berry
Moxie
252 Attack, 252 Speed, 4 Sp Atk
Naive (-Sp Def, +Speed)
Dragon Dance
Dragon Claw
Earthquake
Fire Blast
Salamence is the core of my team. After one dragon dance, he hits 492 speed, outspeeding virtually the entire metagame. After that, he just hits harder and harder, thanks to moxie. Earthquake is for steel types, who are the only pokemon to resist Dragon Claw, and Fire Blast takes care of Skarmory and Ferrothorn, who would otherwise wall Salamence to the end of days. The Lum Berry also lets me get an extra turn against pokemon who would otherwise cripple me with thunder wave or will-o-wisp.

Darmanitan @ Life Orb
Sheer Force
252 Attack, 252 Speed, 4 HP.
Jolly (-Sp Atk, +Speed)
Flare Blitz
Rock Slide
Earthquake
Superpower
I changed Arcanine to Darmanitan, which seems a bit of a shame to me (I really like Arcanine). A slight variant on what Browners suggested, I changed the nature to Jolly, since Life Orb Sheer Force Flare Blitz is going to hurt anyway, and I feel Darmanitan needs a little bit of a speed boost to help it sweep some of the faster pokemon that would otherwise outrun it and kill it off.

Porygon-Z @ Choice Scarf
Adaptability
252 Attack, 252 Speed, 4 HP
Modest (-Attack, +Sp Atk)
Hidden Power (Fighting)
Dark Pulse
Tri Attack
Trick
I'm often wary about using Choice Scarf, since I don't think it gives pokemon an amazing boost. However, Porygon-Z looks like one pokemon that can really use it. Having the scarf allows Porygon-Z to run a Modest nature, boosting his special attack stat to a monumental 404. With that kind of power, and Adaptability kicking in, Tri Attack is going to really hurt anything that doesn't resist it. Dark pulse takes care of Ghost types who resist my STAB, and HP Fighting deals with Steel types. Even better, I can trick my opponents into a set-up move and still have enough power to hit hard.

Espeon @ Choice Specs
Magic Mirror
252 Sp Atk, 252 Speed, 4 HP.
Timid (-Attack, +Speed)
Psyshock
Hidden Power (Fighting)
Grass Knot
Shadow Ball
Not quite so effective as my Choice Specs Trick Espeon back in 4th Gen, but at least now it has an awesome ability. Magic Mirror allows my Espeon to switch in on stealth rocks, spore, and thunder wave and bounce them right back at the opponent. Psyshock has less power than Psychic, but allows me to take out special walls with low physical defense like Chansey. Hidden Power replaces Signal Beam as a counter to dark types, and also hurts Steel types too, which is an added bonus. Grass Knot deals with bulky waters like Quagsire and Swampert, whereas Shadow Ball works well against slower Ghost Types like Dusclops and damages other Psychic types.
So that's it. My fingers are bleeding now, since I was forced to retype this after my computer deleted it all for me. I look forward to your suggestions, thanks in advance.