Yeah, the GBA version was a bit... slaughtered. The statistics are pretty close to the easy mode found in the PSX version, where the game allowed characters to progress to the 99th level of experience. But the stats aren't really random -- character have a chance to get a "weak" or "strong" gain depending on their specific class. (i.e., Fighters are more likely to gain high amounts of STR and HP) Red Mages are somewhat slow to progress, but if you build them up just right, they can replace almost any character. It's just a matter of paying attention to their growth pattern and trying to influence it in another direction.

As for magic, I don't think Temper depends on INT, nor has it ever. It's one of those spells were you get a random value between 8 - 16, I believe. Haste merely increases a character's number of hits, and has a generally static effect. Some people have this misconception that having a Black Mage / Wizard to support melee characters is ideal, but it's really not. There's no difference between Temper / Haste regardless of which class uses them. Aside from this, there's really no point in having a Black Mage for higher level spells, either. You can gain access to unlimted uses of Berserk and Flare through some of the magic items found later on in the game. And really, there's no point in a Black Mage even having the Berserk spell in the first place -- it can only target the caster!

Sorry. End rant.