Normal is a great option, the best pokémon are included in this type (Miltank, Snorlax, Slaking, Ursaring, Porygon2, Blissey, etc.)
With Water you have a lot of option, such as Milotic, Feraligatr, Starmie, Lanturn, Swampert, Gyrados, Vaporeon, etc.
You have a limited choices for ghost, but you can try it (gengar, Dusclops, Misdreavus, Bannete, Sableye, Shedinja)
Dragon would be a good option, if every representant didn´t have an ice weakness (Kingdra isn´t, but it won´t kill THAT much)
Flying is fun, because you can get every type with it (excluding Ghost, Fighting and... I´d include Dark)
Ground is now an variated gorup with Swampert, Claydol, Flygon, etc.
Electric.... poor electric, the only good pokémon in this group are Jolteon (of course), Zapdos and Raikou... maybe electrode.
Ninja kirby´s suggestion for bug is good.