So I'm a long time lurker who's just started actually trying to build teams and I've found the Baton Pass team I'm using has plateau'd on the ladder and I'm still fresh enough on fifth gen that I feel there's some obvious tweaks I can make to make this a lot better, asides from not doing a dedicated BP team. I'm going to post the team with a bit of commentary on each pokemon and then talk about my major problems, and I'd appreciate help with strategies/tweaks to overcome them.
Espeon@Leftovers
Magic Bounce
Timid 36 HP/ 88 Def/ 132 SAtk/ 252 Spd
Baton Pass
Stored Power
Calm Mind
Substitute/Hidden Power Fighting
The star of the show, and the reason I put this team together - Stored Power Espeon is no joke. I'm pretty sure he's got the highest special attack out of anyone that can use the move, and Magic Bounce complements it perfectly, keeping opponents from PHazing him. The EVs were kind of thrown together, but the idea is to make him bulky enough to take a hit or two early game deflecting stuff like entry hazards and leech seed, though in practice he still comes off as too light. I'm thinking of maybe forgoing a lot of speed investment for more bulk. The last slot is a toss-up too, since without Hidden Power fighting he's TTar bait through and through (though thankfully baton pass helps him evade pursuit), though sub helps a lot with early game set-ups on random special attackers, as well as really being the only defense BP has against Dragon Tail.
Vaporeon@Leftovers
Water Absorb
Bold 252 HP/ 212 Def/ 44 SpD
Baton Pass
Wish
Surf
Acid Armor
Basically go to for general bulkiness, with Acid Armor very vitally basically making the rest of the team for the most part protected from priority. Probably the most problematic member of the team, in that Acid Armor is really the only non-BP move in heavy rotation. I'm thinking about maybe changing Surf and Wish into a pseudo BoltBeam combo with HP Electric, since Gyarados between Intimidate and Taunt otherwise walks all over everybody.
Venomoth@Leftovers
Tinted Lens
Timid 252 HP/ 4 SAtk/ 252 Spd
Baton Pass
Quiver Dance
Sleep Powder
Bug Buzz
Despite his position here, probably the most common lead since he makes an awesome passing partner with Espeon. One Quiver Dance basically is sometimes enough for Espeon to just go medieval on the rest of the opponent's team, and Bug Buzz provides great coverage on most of the dark types that otherwise completely wall Espeon (I've had Stored Powers running off surprisingly low amounts of boosts 2KO Jirachi). Additionally, being one of the few Poison Types with Baton Pass is a huge boon, since it means that probably the most lethal hazard to the team can be removed (also the only spinners with baton pass are Smeargle and lolSpinda).
Gliscor@Toxic Orb
Poison Heal
Impish 252 HP/ 184 Def/ 72 Spd
Baton Pass
Earthquake
Agility
Protect
Basically, my go-to for speed passing when everything's hitting Venomoth too hard. Being a mono-attacker is probably his biggest problem, especially since so much is immune to Earthquake. Protect is probably the least necessary move here, and he really could use Taunt or Stone Edge there, though without it all of a sudden it seems like every attack with a secondary chance to paralyze or burn hits him before the orb can activate, especially when he's a speed passing lead. Maybe run him with leftovers to absorb poison when it comes and forgo protect entirely?
Medicham@Air Mail
Pure Power
Jolly 252 Atk/ 4 Def/ 252 Spd
Baton Pass
Acupressure/Bulk Up
High Jump Kick
Zen Headbutt
The only fighting type with Baton Pass, and unfortunately he's frail as shit and lacking in priority. Air Mail is to make trick users rage, Acupressure is the best move in the game, though Bulk Up is probably more reliable (though +1 defense does nothing for his frailty). Basically, he has the potential to either destroy most of the shit that gives Espeon trouble or fall flat killing himself with High Jump Kick on the opponent's Ferrothorn or something.
Scizor@Leftovers
Technician
Adamant 252 HP/ 40 Atk/ 216 SpD
Baton Pass
Swords Dance
Bullet Punch
Bug Bite
By far the most powerful priority available with Baton Pass, which basically keeps a ton of random frail fast stuff from breaking the chain early on. Probably his only real problem is that asides from that he's slow as shit even with a +2 speed boost making it easy for Fire Types to break the chain.
So that's the team. The idea is a bulky baton pass team that keeps on building up any boost possible making the team more impenetrable until it has enough boosts for Espeon to kill everything (remember, even without Special Attack boosts Stored Power with the equivalent of two maxed out stats (or +12) is more powerful than Lickilicky's explosion). A huge problem results from Espeon not having enough immediate bulk, which especially can make it hard to utilize Magic Bounce to keep stuff like Stealth Rock and Leech Seed off the chain. yeah I know BP chains went out of style at some point but Stored Power Espeon is terrifying, holding the most potentially powerful move in the game, and I think a chain is the best way to ensure that it works.
Espeon@Leftovers
Magic Bounce
Timid 36 HP/ 88 Def/ 132 SAtk/ 252 Spd
Baton Pass
Stored Power
Calm Mind
Substitute/Hidden Power Fighting
The star of the show, and the reason I put this team together - Stored Power Espeon is no joke. I'm pretty sure he's got the highest special attack out of anyone that can use the move, and Magic Bounce complements it perfectly, keeping opponents from PHazing him. The EVs were kind of thrown together, but the idea is to make him bulky enough to take a hit or two early game deflecting stuff like entry hazards and leech seed, though in practice he still comes off as too light. I'm thinking of maybe forgoing a lot of speed investment for more bulk. The last slot is a toss-up too, since without Hidden Power fighting he's TTar bait through and through (though thankfully baton pass helps him evade pursuit), though sub helps a lot with early game set-ups on random special attackers, as well as really being the only defense BP has against Dragon Tail.
Vaporeon@Leftovers
Water Absorb
Bold 252 HP/ 212 Def/ 44 SpD
Baton Pass
Wish
Surf
Acid Armor
Basically go to for general bulkiness, with Acid Armor very vitally basically making the rest of the team for the most part protected from priority. Probably the most problematic member of the team, in that Acid Armor is really the only non-BP move in heavy rotation. I'm thinking about maybe changing Surf and Wish into a pseudo BoltBeam combo with HP Electric, since Gyarados between Intimidate and Taunt otherwise walks all over everybody.
Venomoth@Leftovers
Tinted Lens
Timid 252 HP/ 4 SAtk/ 252 Spd
Baton Pass
Quiver Dance
Sleep Powder
Bug Buzz
Despite his position here, probably the most common lead since he makes an awesome passing partner with Espeon. One Quiver Dance basically is sometimes enough for Espeon to just go medieval on the rest of the opponent's team, and Bug Buzz provides great coverage on most of the dark types that otherwise completely wall Espeon (I've had Stored Powers running off surprisingly low amounts of boosts 2KO Jirachi). Additionally, being one of the few Poison Types with Baton Pass is a huge boon, since it means that probably the most lethal hazard to the team can be removed (also the only spinners with baton pass are Smeargle and lolSpinda).
Gliscor@Toxic Orb
Poison Heal
Impish 252 HP/ 184 Def/ 72 Spd
Baton Pass
Earthquake
Agility
Protect
Basically, my go-to for speed passing when everything's hitting Venomoth too hard. Being a mono-attacker is probably his biggest problem, especially since so much is immune to Earthquake. Protect is probably the least necessary move here, and he really could use Taunt or Stone Edge there, though without it all of a sudden it seems like every attack with a secondary chance to paralyze or burn hits him before the orb can activate, especially when he's a speed passing lead. Maybe run him with leftovers to absorb poison when it comes and forgo protect entirely?
Medicham@Air Mail
Pure Power
Jolly 252 Atk/ 4 Def/ 252 Spd
Baton Pass
Acupressure/Bulk Up
High Jump Kick
Zen Headbutt
The only fighting type with Baton Pass, and unfortunately he's frail as shit and lacking in priority. Air Mail is to make trick users rage, Acupressure is the best move in the game, though Bulk Up is probably more reliable (though +1 defense does nothing for his frailty). Basically, he has the potential to either destroy most of the shit that gives Espeon trouble or fall flat killing himself with High Jump Kick on the opponent's Ferrothorn or something.
Scizor@Leftovers
Technician
Adamant 252 HP/ 40 Atk/ 216 SpD
Baton Pass
Swords Dance
Bullet Punch
Bug Bite
By far the most powerful priority available with Baton Pass, which basically keeps a ton of random frail fast stuff from breaking the chain early on. Probably his only real problem is that asides from that he's slow as shit even with a +2 speed boost making it easy for Fire Types to break the chain.
So that's the team. The idea is a bulky baton pass team that keeps on building up any boost possible making the team more impenetrable until it has enough boosts for Espeon to kill everything (remember, even without Special Attack boosts Stored Power with the equivalent of two maxed out stats (or +12) is more powerful than Lickilicky's explosion). A huge problem results from Espeon not having enough immediate bulk, which especially can make it hard to utilize Magic Bounce to keep stuff like Stealth Rock and Leech Seed off the chain. yeah I know BP chains went out of style at some point but Stored Power Espeon is terrifying, holding the most potentially powerful move in the game, and I think a chain is the best way to ensure that it works.