Ive had really good luck putting all starting points into str with my knight, and then utilizing equipment for whatever is lacking (mainly constitution) and so forth. what that gives you is a tank that can take a beating and dish it out double. but yes warrior skills first.
for mages (up to where i am) i have 2 wizards/elementalists (whatever they are, the stock builds are irrelevant for me) that use aero/hydro and aero/pyro. both have tele, blitz bolt and staff of magus, and both utilize destruction while the hydro has healing and what i see as support. the lightning is good all around, with exceptions of course.
my forth is a ranger that specializes in aoe. cloud attacks, explosions, ricochet. for example if hes not hitting more than one opponent, i'll have him hold off on his turn and have a mage or two tele one or 2 others into range and *hope* they stay put
or tele enemies into close quarters with knight and unleash the whirlwind or battering ram
all in all your best off finding what works best for you, and what strategies work best as well. to get that you may end up restarting a few times. im on my 4th reset after dumping probably 20+ hours in total for my first 3 tries. and now im around 35-40+ hours and hoping i can find the respec guy fast
