[Taqwus]

Range does matter. Some of the high-precision / long-range spells do tend to target Big Nasties especially powerful commanders, 'tho; Curse comes to mind (watch out for those lizard provinces!).

Two issues about commander targeting, 'tho: realism and gameplay. To target leaders specifically implies that they can somehow be noticed and identified, despite frequently being near the far end of the fray with possibly a large melee in the way. Another realism bit is that a mage might target units that seem more likely to threaten him personally (are closer, say) or otherwise stand out. You're looking at the battle from a god's eye view in relative personal safety (unless you're playing on a laptop in the middle of a gangwar crossfire or something like that) and with the luxury of being able to take advantage of perfect information and without time pressure (rather than looking into a chaotic melee and wondering whether you're going to live). Some seemingly lousy targeting seems permissable.

Gameplay -- would tilt balance towards certain long-range / precise spells like Incinerate, Soul Slay. Magic would make mid/late battles gunfights, and this would be particularly evil considering that all defending mages would get first draw...