Haven't been in doubles very long, this is mainly made for Battle Spot but also will hopefully take me through the Maison, so it's meant to be 4v4. This is version 1.1 (I have switched Rock Slide for Poison Jab on Scraggy due to the large number of Fairies and Brelooms in the Battle Spot Doubles playlist).
Here's the team as it is:
All Pokemon have 0 IV in Speed

Slowbro @ Sitrus Berry
Ability: Oblivious
Relaxed Nature, 252 HP/252 Def/4 SpD
Trick Room
Light Screen
Slack Off
Protect
Obvious necessity, the TR setter. Pure support, so I run Oblivious over Regenerator to prevent him from being Taunt-fodder. Instead, he becomes Taunt-Bait, and lets me get a free turn from typical Taunt Pokemon like Sableye. Typical order is TR->Light Screen->Slack Off/Protect until TR runs out. Light Screen and Slack Off take advantage of Slowbro's physical bulk so well, Slowbro is almost always alive until either the last turn, or until the game will be decided before TR runs out again.

Scrafty @ Assault Vest
Ability: Intimidate
Brave Nature, 252 HP/252 Atk/4 SpD
Fake Out
Drain Punch
Crunch
Poison Jab
Slowbro's typical partner-in-crime. Fake Out hits obvious threats (Fairies to kill Scrafty, Special hitters that may threaten Slowbro turn 1, spore users, etc.) to guarantee the TR gets up. Intimidate plus Slowbro's Light Screen and Drain Punch mean Scrafty is going to put more of a dent in your team then you will mine. Crunch is an alternate STAB, because I intend to Kalos Breed this and Kalos Scrafty cannot have Knock Off. I used Rock Slide to attempt to cause flinches and deal spread damage since a field spot is usually taken by Slowbro, but too many Fairies and Brelooms caused me to see the value in Poison Jab.

Mawile @ Mawilite
Ability: Intimidate
Brave Nature, 252 HP/252 Atk/4 SpD
Power-Up Punch
Play Rough
Sucker Punch
Rock Slide
When Scrafty goes down, his less bulky but stronger friend Mawile comes to the field. I will also tend to switch if I think a new threat needs intimidate, allowing Scrafty to come in again for another Fake Out. But the switching is not done often. Power-Up Punch gets me a small Atk boost w/o sacrificing a turn of Damage. Play Rough is the main STAB, while Sucker Punch lets Mawile do something if TR runs out. Rock Slide deals w/ Talonflame while TR is up, as most Talonflame won't use a Flying move on a Steel Pokemon.

Aegislash @ Weakness Policy
Quiet Nature, 252 HP/252 SpA/4 SpD
King's Shield
Shadow Ball
Hidden Power (Fighting)
Flash Cannon
Because Physical Pokemon can't handle it all. If I can bait in a SE hit in Shield Form, Weakness Policy turns Aegislash into a real monster under TR. Shadow Ball and Flash Cannon are basic STAB, each with the added benefit of sometimes lowering SpD so he'll hit harder. HP is for coverage. King's Shield protects him when TR's down for a turn, and if done right adds to his bulk. A properly-timed KS under Light Screen means I might not care about the SE hit required for Weakness Policy.
So this is the main core, I normally do not switch. But, 2 of them are hard-weak to Fire, so if I see those around I tend to switch those Steel-Types for these guys, and I KNOW they need work as I chose them arbitrarily.

Pangoro @ Life Orb
Ability: Iron Fist
Brave Nature, 252 HP/252 Atk/4 SpD
Power-Up Punch
Crunch
Poison Jab
Taunt
Meh, an alternate second physical hitter (that's not weak to Fire/Ground) for when Scrafty goes. Iron Fist is mainly because I couldn't see Mold Breaker being useful unless I face Justified here. Power-Up punch and Crunch gives him similar coverage to Mawile, while Poison Jab helps against the Fairies he's 4x Weak too. Taunt is kind of filler, never had an issue in any of the situations I've actually used Pangoro for.

Sylveon @ Choice Specs
Ability: Pixelate
Quiet Nature, 252 Hp/252 SpA/4 Def
Dazzling Gleam
Psyshock
Shadow Ball
Echoed Voice
Meh, again, and alternate. When I fear Aegislash will be destroyed by Dark or Fire. Dazzling Gleam is the usual move, but Psyshock and Shadow Ball are decent alternatives if Fairy isn't an option. In the rare case I have enemies incapacitated (rest/setting up) I put on Echoed Voice for it's Pixelate boost, but I doubt it'll ever get more than 2 turns out of it. Mostly just needed a 4th attack move because Choice.
So, any advice to improve upon this team? Problems I know I have already but would love solutions to:
Spore users. Though they never seem to target Slowbro, they always get my actual attacker.
Extended Battles: I seem to peeter out a bit if the enemy lasts too long, despite my focus on Power in all but Slowbro.
Perish Trap. If Scrafty goes, I lose to that. In fact, I often have to sac the Fake Out for Crunch if I see a Gengar. I can beat it, but only if Gengar doesn't see Crunch coming.
Here's the team as it is:
All Pokemon have 0 IV in Speed

Slowbro @ Sitrus Berry
Ability: Oblivious
Relaxed Nature, 252 HP/252 Def/4 SpD
Trick Room
Light Screen
Slack Off
Protect
Obvious necessity, the TR setter. Pure support, so I run Oblivious over Regenerator to prevent him from being Taunt-fodder. Instead, he becomes Taunt-Bait, and lets me get a free turn from typical Taunt Pokemon like Sableye. Typical order is TR->Light Screen->Slack Off/Protect until TR runs out. Light Screen and Slack Off take advantage of Slowbro's physical bulk so well, Slowbro is almost always alive until either the last turn, or until the game will be decided before TR runs out again.

Scrafty @ Assault Vest
Ability: Intimidate
Brave Nature, 252 HP/252 Atk/4 SpD
Fake Out
Drain Punch
Crunch
Poison Jab
Slowbro's typical partner-in-crime. Fake Out hits obvious threats (Fairies to kill Scrafty, Special hitters that may threaten Slowbro turn 1, spore users, etc.) to guarantee the TR gets up. Intimidate plus Slowbro's Light Screen and Drain Punch mean Scrafty is going to put more of a dent in your team then you will mine. Crunch is an alternate STAB, because I intend to Kalos Breed this and Kalos Scrafty cannot have Knock Off. I used Rock Slide to attempt to cause flinches and deal spread damage since a field spot is usually taken by Slowbro, but too many Fairies and Brelooms caused me to see the value in Poison Jab.

Mawile @ Mawilite
Ability: Intimidate
Brave Nature, 252 HP/252 Atk/4 SpD
Power-Up Punch
Play Rough
Sucker Punch
Rock Slide
When Scrafty goes down, his less bulky but stronger friend Mawile comes to the field. I will also tend to switch if I think a new threat needs intimidate, allowing Scrafty to come in again for another Fake Out. But the switching is not done often. Power-Up Punch gets me a small Atk boost w/o sacrificing a turn of Damage. Play Rough is the main STAB, while Sucker Punch lets Mawile do something if TR runs out. Rock Slide deals w/ Talonflame while TR is up, as most Talonflame won't use a Flying move on a Steel Pokemon.

Aegislash @ Weakness Policy
Quiet Nature, 252 HP/252 SpA/4 SpD
King's Shield
Shadow Ball
Hidden Power (Fighting)
Flash Cannon
Because Physical Pokemon can't handle it all. If I can bait in a SE hit in Shield Form, Weakness Policy turns Aegislash into a real monster under TR. Shadow Ball and Flash Cannon are basic STAB, each with the added benefit of sometimes lowering SpD so he'll hit harder. HP is for coverage. King's Shield protects him when TR's down for a turn, and if done right adds to his bulk. A properly-timed KS under Light Screen means I might not care about the SE hit required for Weakness Policy.
So this is the main core, I normally do not switch. But, 2 of them are hard-weak to Fire, so if I see those around I tend to switch those Steel-Types for these guys, and I KNOW they need work as I chose them arbitrarily.

Pangoro @ Life Orb
Ability: Iron Fist
Brave Nature, 252 HP/252 Atk/4 SpD
Power-Up Punch
Crunch
Poison Jab
Taunt
Meh, an alternate second physical hitter (that's not weak to Fire/Ground) for when Scrafty goes. Iron Fist is mainly because I couldn't see Mold Breaker being useful unless I face Justified here. Power-Up punch and Crunch gives him similar coverage to Mawile, while Poison Jab helps against the Fairies he's 4x Weak too. Taunt is kind of filler, never had an issue in any of the situations I've actually used Pangoro for.

Sylveon @ Choice Specs
Ability: Pixelate
Quiet Nature, 252 Hp/252 SpA/4 Def
Dazzling Gleam
Psyshock
Shadow Ball
Echoed Voice
Meh, again, and alternate. When I fear Aegislash will be destroyed by Dark or Fire. Dazzling Gleam is the usual move, but Psyshock and Shadow Ball are decent alternatives if Fairy isn't an option. In the rare case I have enemies incapacitated (rest/setting up) I put on Echoed Voice for it's Pixelate boost, but I doubt it'll ever get more than 2 turns out of it. Mostly just needed a 4th attack move because Choice.
So, any advice to improve upon this team? Problems I know I have already but would love solutions to:
Spore users. Though they never seem to target Slowbro, they always get my actual attacker.
Extended Battles: I seem to peeter out a bit if the enemy lasts too long, despite my focus on Power in all but Slowbro.
Perish Trap. If Scrafty goes, I lose to that. In fact, I often have to sac the Fake Out for Crunch if I see a Gengar. I can beat it, but only if Gengar doesn't see Crunch coming.