One thing that has become clear to me in the magic thread is that we can't just design a magic system in isolation. There are many awesome ways to implement magic. The problem will be devising a method for magic that is sufficiently cool, but also balanced against martial skills. The easiest way to make cool magic viable is to make martial characters cool as well.
The simplest way is to just have an attack; walk into an enemy, attack them. However, unless magic is similarly as simple as "cast spell to damage enemy", this is unlikely to stack up well.
One way to spice it up is to (stealing terminology from D&D 3.5's tome of battle) use maneuvers and stances.
a maneuver is an activated ability that does something beyond a simple attack. It might hit multiple people, stun or slow an enemy, push an enemy around, allow you to move while doing the attack, attack multiple times, give penalties to the opponent, adding extra damage, etc
a stance is a passive state you enter into that gives you bonuses, like being faster, or improving your defenses, etc.
You can have these require equipment (this type of attack is only doable with a hammer, you need a shield to use this defensive stance, this flurry attack requires two weapons, etc), or even have some granted by your equipment. a ranged character may have their own set of possible maneuvers. Having different types of maneuvers available would be a great way to distinguish types of weapons.
You could have every maneuver you know be available, or restrict yourself to a set you have made active, or a compromise where a set is available via quick-bar or hotkeys and the rest are buried in menus.
They also have the advantage of deepening the tactical side of the game. Its no longer "move places and make attacks", but choosing the right abilities.
There are many ways to manage these abilities. One way which ties into things mention already would be for them to consume stamina. They could also operate on a card-based system, where each maneuver is an action you have a card for, which you have to expend to use it. Another type of action can be used to refresh your cards. Another way is a cooldown, where you can't use an ability for a certain time after activating it. A fusion of multiple methods is also feasible, such as cooldowns with a stamina cost, where the stamina limits your overall use of the abilities and the cooldown enforces a variety to be used.
You could also put these abilities into classes, like these are "fast strikes" and these are "crushing blows" and you pick one of each category. This seems more sensible for a real-time game though.
You could also have a combo based system. Imagine a fighting game like street fighter, only rather than being twitch based, you get one key press each turn. do a quick attack, quick attack, hard attack, and you get a more powerful attack at the end. This could probably yield and interesting combat system, but I don't know that it would serve VQ well.