i tend to have more physical fighters than magical. i often have 4 fighters and two spellcasters. one spellcaster for healing and the other for offensive magic. i usually find the spellcasters more useful though. high level spells can do over 100 damage to multiple targets and can dramtically weaken loads of targets which can then be easily k.oed by a fighters attack. ill vote for a combination of the two because without my mages my fighters wouldnt be doing too good. also haste is a very useful spell.

sage/alchemist is one of the best combinations on the game because they have the death spell as well as other high level spells which can match the power of a black mage. and raise is great because it revives everyone in the targetting area as well as restoring large amounts of HP to k.oed and conscious units.

and for physical. gladiator/dragoon is possibly the best. long range attacks as well as insane power and bonecrusher with a spear and 2 space range is just plain powerful. if i had a party of 3 gladiator/dragoons. 2 sage/alchemist and a whitemage/time mage (for healing before the sages learn raise.) i would storm through the game unopposed by nearly any enemy.