I've been mulling this over in my head for a while now, and I think I've come to the conclusion that mages are just really, really wussy. At lower levels, given even basic equipment, a fighter, a thief, a cleric, or even a priestess is going to wipe the floor with a mage. Other magic users (like the cleric) get weapons and armor, or (like the priestess and witch) get access to a whole lot of spells. The mage, on the other hand, has access to... almost nothing. If a battle lasts more rounds than the mage has levels, he's pretty much going to be sitting in the back saying, "No no, you go ahead, I'll just sit here, thanks."
While mages can specialize - prepare spells specifically for the primary task at hand - they need a lot of time and money to do that, especially at later levels. I realize that high-level mages are going to have more powerful spells, and a lot more of them; a 5th level mage has a third level spell, and 5 spells total. But compared to the equally-unarmored Priestess, he's a spell behind, and the priestess gets to cast any spell she wants. And even a specialized 8th level mage can't prepare for everything; that stone-to-flesh you spent weeks preparing is great until you realize you just used up your spell slots fighting orgres. Oops.
In short: mages get the short end of the stick. Once they've shot all their spells, they have nothing but a 1d6 staff to their name. Lore makes them out to be powerful masters of the arcane, but in reality, they are one-shot wonders. For a campaign with long battles, that means mages are going to be passed over with some regularity. Mages are great for utility, but terrible for battles - in fact, much worse than the cleric, even though the cleric is supposed to be the support character.
However, in D&D (note, I've not actually played D&D, just read about it... I do that a lot) there exists a type of spell called a cantrip: a low-level spell that wizardy-types can shoot all day long. That would mean that a wizard that locked a door and tossed a few magic missiles at a target in the morning can still be relevant by lunchtime; sure, a cantrip doesn't do much in the way of damage, but running in swinging your staff is going to get you killed.
In ACKS, there is no cantrip, but I've already introduced 0th level spells (spells of 1/2 spell point or less). At such a low level, it's not going to do much damage, but it's better than nothing; you can make a 1d4 attack with a save at range 15' for exactly 1/2 a point; not as good as a crossbow, but it'll hit well-armored targets. Or, he could summon a single centipede for a turn, as long as he concentrates and the centipede doesn't make its saving throw (0.43 spell points).
Any arcane type (which includes Mages, Gnomish Tricksters, Zaharan Ruinguards, and Elvish Spellswords, but not Clerics, Bladedancers, or Witches) has one of these 0th level spell slots at level 1 (though partial mages get their cantrips later; 2/3 or 1/2 mage at level 2, 1/3 mage at level 3). Cantrip slots are improved as usual by INT bonus; that means a mage with INT 18 gets 4 cantrips. These cantrips can be used at will. Research can be done on cantrips as usual; however, the spell must always be a 1/2 point spell or less - no research breakthroughs. For the purpose of math (for cost and time), treat the spell as 1/2 level. A mage can only cast the cantrip(s) he has; if he wants something else, he has to research it. Finally, cantrips do have an added requirement: no worn armor, no readied weapon (except a staff, since that can act as a focus). A Ruinguard or Spellsword will have to remove their armor and drop their weapon(s) to be able to cast a cantrip. Then again, their weapons and armor usually are better than a cantrip anyway.
What do you think - does this make a mage too powerful? Or does it balance that gap between low-level mages and low-level fighters?