I've beaten the Elite 4 and caught Kyurem and Reshiram, so this is really my post-game team. It's practical more than anything - allows me to travel almost anywhere and a specific Poke designed for catching. I only really travel with 4 Pokemon. I always keep free slots for training or looking quickly at the stats of new captures.
100 - Parasect - nickname: In The Rye (really funny joke, I assure you!)
Item: Amulet Coin
Ability: Dry Skin
• False Swipe
• Giga Drain
• Rock Smash (Used to be Aromatherapy - I think I need to switch back)
75 - Serperior - nickname: n/a - item: Miracle Seed
• Leaf Storm
• Leaf Blade
76 - Golduck - nickname: n/a - item: Mystic Water
• Soak (one of my favourite strategies for catching awkward Pokes is to change them to water and use Net Balls - plus it usually ruins the target's STAB)
79 - Unfezant - nickname: n/a - item: Sharp Beak
Ability: Big Pecks
• Air Slash
My Parasect was actually created in HeartGold and pulled in to help me complete my Pokedex. Before the next game comes out I'm planning to breed an Adamant Paras to give False Swipe a bit more sting.