The bow is the most important weapon in all the MM games. Learn to shoot on the retreat, and whilst moving sideways, and you'll be able to do an enormous amount of damage without your party suffering undue damage.

I like magic-heavy parties. My preferred party for the light path is APCS. The archer is just about good enough at disarming to prevent too much damage from chests, particularly if you can find some boosters for him. The paladin is a back-up healer and is also insurance against the weakness of the magic users in the early game. The cleric is the main healer, and gives the invaluable GM Protection from Magic - that's important in this game, believe me, so I would always GM body magic. GM Prot Magic gives protection against a range of instant death or disablement magics. The sorcerer is there for Fly and the travel spells, especially Lloyd's Beacon. Most important, your whole party will eventually gain access to that most important of all combat spells for a Light party - Paralyze.

The preferred dark path party is ACSS. You have to be careful in the early stages with this lot. Lacking the paladin's melée capabilities, the party tends to be fragile at the beginning of the game. But later on, when they start getting access to the high-level dark magic combat spells, they become enormously powerful. It is however worthwhile to keep a decent supply of healing potions and scrolls to repair your cleric when he/she gets clobbered.

In developing my sorcerer in this game, I would put my spell points first of all into Air. Then Water, then Fire, and last of all Earth. The Fly spell is extremely useful and you can get it reasonably early, and they have some decent combat spells in there - lightning bolt is not to be sneezed at. You have to reach GM before you can use LB. But until you have you have all the core skills up to expert, don't develop any skill beyond that. That doesn't apply if you have two sorcerers, of course. Then you can develop two magic skills in one and the other two magic skills in the other.

I would always get my magic users up to their maximum reasonable skill level in a melée weapon. Mana runs out; a mace may not work quite as well, but it always works. Also I would always get one person up to expert in perception. It's useful to see trapped areas. Also, I can't remember exactly where, but I seem to remember you actually need it in one or two places.