one mage with all 4 schools of elemental magic is all that is needed and higher than level 4 isnt all that essential but 4th level is plenty of spell ability, Madora is not nearly as good as a Knight/fighter that is a PC and built correctly, optimized to only be an ass kickin name taking meat shield.

My experience has been that Hydro and Aero are better spell fields than Fire or Geo and that Witchcraft is not needed at all. But get em all they have uses and diversity is nice.

Not really a huge fan of Jahan or Madora. SO thats a personal preference others do not have, I also dont think more than one spellcaster and one fighter and one rogue is a necessity, I play a party of 3 usually since I lone Wolf the fighter.