I figure its time I came out and post my current team, and see what your thoughts are on it.
I've spent some time over the recent months experimenting with teambuilding and battling on Showdown. Some mons have come and gone in that time, some moves were changed and swapped out, and the end result was this team, which is now pretty much fully realized in my copy of Pokémon Y, lame nicknames included.
Battle Format: VGC 2014 Doubles
Sableye@Sitrus Berry, AKA: "Stinkeye"
252 HP/252 SpD/4 Def
This is the team's main disruptive support. It's by far one I will most often lead with, particularly if I can't for sure predict the opponent's leading pair based on what I see in the preview. It makes a good scout in that respect, and Foul Play is a great way to bring some offense to the table.
Delphox@Charcoal, AKA: "Wizbang" (open to alternative items)
Blaze (considering changing to Magician)
252 SPA/252 Spe/4 HP
This is the team's fire sweeper. Normally I like to work it in conjunction with the Sableye to get off a Sunny Day, as well as apply a burn to potential physical threats to the Delphox. I'm still somewhat on the fence whether to keep Psyshock or switch it out for Psychic, since I've had reasonably comparable success using both. The main draw of Psyshock over Psychic is if the opponent sees a Special Sweeper on the field, and sends in a Special Wall to bear the brunt of its attacks, like a Goodra for example. Since Psyshock goes against the target's Physical Defense instead, it's a way to mitigate such a tactic, but at the price of slightly weaker raw attack power.
It currently has Blaze in my copy of Y, but I have run Delphox with Magician on Showdown, and had a lot of fun pulling items out of opponents' mons' hands. I might change it if I can get a replacement with its hidden ability.
Inner Focus (Adaptability)
252 SpA/252 Spe/4 HP
Fairly straightforward special sweeping Mega Lucario. I decided to go with a special sweeper as opposed to physical mainly because of how prevalent physical attack is in the metagame currently, and the measures many players take to cut down an opponent's physical attack power and/or bolster their physical defenses.
252 HP/68 SpD/188 Spe
This is the team's Trick-or-Treat setter/Seeder/Secondary Burner. True, it's not the super-sized grass wall, but there's a specific reason for that. It has the small size, the jolly nature, and 188EVs in speed for one important purpose: in order to barely outrun the Lucario listed above. Since speed changes for Mega evolutions don't apply until the turn after, my Lucario can Mega evolve, receive the Ghost typing from Gourgeist, and fire an adaptability STAB Shadow Ball at its target in one fell swoop. This particular tactic is used primarily against bulky psychic types, especially things like Prankster support Meowstics or trick room setters, as well as any vulnerable ghost type target that is still outpaced by a normal Lucario's speed. The extra speed is also nice to outrun many fighting type responses often sent out vs. Lucario, granting the fighting type immunity before the opponent can land their blow.
Weavile@Life Orb, AKA: "Bandit"
252 Atk/252 Spe/4 HP
Dragon Hunter. With how prevalent Dragon types are in the metagame, especially such mons as Salamence and Garchomp, Ice Shard Weavile is a natural choice to combat that with. The Trick-or-Treat Gourgest above opens up another option though by painting a target with the ghost typing (a target which otherwise has no typing weakness I can readily exploit) and letting Weavile's Night Slash take care of it afterward.
Jolteon@Magnet, AKA: "Blitz"
252 SpA/252 Spe/4 HP
Volt Switch (considering changing, maybe a status infliction)
Bird Zapper. Outruns Mega Charizard Y, resists Talonflame's Brave Bird, OHKO's both of them. It's primarily there to fill a niche, albeit a common niche; to neutralize the threats of the two highly popular, prevalent, and dangerous flying fire types listed above. Yes, Mega Manectric could probably fill this niche better and with greater coverage options, but I already have a mega evolution on this team. That said, this Jolteon can and has functioned well outside that niche. Jolteon often comes out as an opener alongside Sableye, where it wrecks its niche targets if the opponent opens with them, or provides further disruptive support with Thunder Wave. Shadow ball is there for coverage, sometimes taking advantage of Gourgeist's Trick-or-Treat if the opportunity is available for it.
I am seriously considering switching Volt Switch for an alternative move though. The times I'd normally use Volt Switch are if Jolteon's niche targets that I saw in team preview didn't open the match and I need to keep him safe and/or to add extra damage while I put in a mon I have in reserve that fits the situation better. And even then, it doesn't do too much besides tack on a chunk of damage during a swap-out. And heck, if there's a lighting-rod partner on the opposing team it's more than likely going to being swapped out anyway, and Volt Switch does no good there. In place of Volt Switch, I might have either Charm or Baby-Doll Eyes to cut down on the opponent's attack; Charm for the -2 to attack, and Baby-Doll Eyes for the +1 Priority.
Remember, the battle format intended for this team is VGC 2014 Doubles. Please keep that in mind when offering critiques and suggestions. Thanks!