Looks like you've got a good team here. Here are my suggestions:
For Swampert, I'd prefer Ice Beam over Hydro Pump. Hydro Pump has a lower accuracy than Ice Beam, so since Swampert is more on the defensive end you'll want a move that's reliable and can take out deadly threats.
If you're comfortable with Jolteon as it is, then leave it. My only suggestion is to take out either Thunderbolt or Charge Beam(maybe Thunderbolt instead because you have Lifore Orb plus the possibility of raising your Sp. Attack stat) and replace it with Magnet Rise because Earthquake(and any other ground type move) is going to OHKO Jolteon no matter what. Jolteon has no other weaknesses and should be able to take at least 2 non-ground hits.
As for Gyarados, Leftovers is more important than Life Orb because you've got Dragon Dance. With one DD, you hard. With two, OHKO's are definatly in sight. I think I'd go with Ice Fang over Stone Edge because it's a more versatile move. Ice Fang would be your only Ice move if you stay with Hyrdo Pump for Swampert. Even if choose Ice Beam for Swampert, having more than one Ice move is very effective.
For Heracross, I think Pursuit is the better move. When you send Heracross in to counter another pokemon, your opponent will most likely switch and that's where Pursuit shines. Also, Pursuit goes better with Choice Scarf because in the event that your opponent does switch, you're stuck with Pursuit along with any other move. Compared being stuck with Pursuit or stuck with Night Slash against a pokemon that can withstand them won't matter because you'll most likely want to switch.