Alright, Six pokes and a team. I love making teams, so two suggestions, All using pokemon caught before the elite four. Team well thought out and balanced, and also fun!:
Miltank@Body Slam/Zen Headbutt/Milk Drink/Captivate or Heal Bell
Ampharos@Signal Beam/Discharge/Thunder Wave/Charge
Pinsir@ X-Scizzor/Brick Break/Thrash/Swords Dance
Dragonite@Extremespeed/Aqua Tail/Thunder Wave/Dragon Rush
Mr. Mime@Pyschic/Shadow Ball/Substitute/Reflect
Feraligatr@Crunch/Ice Fang/Slash/Earthquake
Team let's dance in the Rain!:
Kingdra@(Swift Swim)Rain Dance/Hydro Pump/Surf/Dragon Pulse
Poliwrath@Rain Dance/Hypnosis/Brick Break/Surf
Mantine@(Swift Swim) Rain Dance/Signal Beam/Surf/Confuse Ray
Quagsire@Rain Dance/Surf/Earthquake/Yawn
Parasect@(Dry Skin)@ Slash/Spore/Cross Poison/Stun Spore
Kangaskhan@Outrage/Dizzy Punch/Crunch/Earthquake