I recently new gamed pearl and have managed to get through fairly well with a team of 5. I'm currently training up in Iron Island before i have a go at taking on the Canalave gym;
Cyan - Empoleon
Male, Torrent, Hardy, L43
Surf
Brine
Steel Wing
Peck
I plan to replace Peck with Drill Peck, other than that unsure if i'm going to change him
Domino - Skuntank
Male, Aftermath, Docile, L40
Poison Jab
Toxic
Night Slash
Flamethrower
My first time using one of these guys and he's proved his worth. I don't have any intention of changing him as i'm pleased with his set
Lucy - Luxray
Female, Intimidate, Naive, L37
Tackle
Spark
Change
Crunch
Used a Luxray when i originally got Diamond and though they were awesome pokemon, undecided what i'm gonna have as her final move set, obviously intending to replace Tackle but haven't decided what with yet
Bell - Roselia
Female, Poison Point, Quiet, L36
Ingrain
Magical Leaf
Toxic Spikes
Stun Spore
I may reteach her Leech Seed when i can get a heart scale (caught her as a Budew and she evolved too late to learn it) other than that, i haven't really decided what i'm teaching her before i evolve her
Flopsi - Buneary
Female, Run Away, Adamant, L36
Jump Kick
Dizzy Punch
Foresight
Quick Attack
I plan to teach her Return when she evolves into Lopunny (soon hopefully), other than that, i haven't decided if she's gonna be replaced or not by another normal type or another useful pokemon
As mentioned, i intend to train them up before taking on Canalave gym etc. I just caught a Steelix at L34 which i'm considering using (as i love them), other than that, i'm open to suggestions for change and welcome them =] Subject to change overtime too