I've had 2 parties, both of which I've found quite effective. My second however, is only at the Serpent Temple, so they aren't very advanced yet, but I have high hopes for them.
Here's my first party:
Human (F) Warrior/Paladin/Valkyrie
Dwarf (M) Warrior/Barbarian
Whiskah (M) Warrior/Samurai/Zenmaster
Human (M) Priest/Monk/Ninja/Zenmaster(Yes I know, 2 Zenmasters, I cheated, it was fun though

)
Human (F) Rogue/Ninja/Assassin
Elf (M) Wizard/Warlock/Ranger/Paladin
Here's my current one, only my Warrior is on his third role, and all but one of my wizard's is on it's second, but I'll post what I want them to be in the future:
Human (M) Warrior/Barbarian/Paladin/Samurai/Assassin(Maybe)
Omphaaz (M) Priest/Monk/Paladin(If I find some good Omphaaz Armor)/Zenmaster
Whiskah (M) Priest/Monk/Ranger
Ratling (M) Rogue/Ninja/Assassin
Elf (F) Wizard/Samurai/Ninja or Monk/Valkyrie
Pixie (F) Wizard/Warlock/Bard
I'm not sure yet if I want to cheat and have TWO Assassins but if I do the Human won't change until the end or very close to it.
-Jafin