Casting Styles would be chosen just like you choose the target (self, target, touch). Each casting style would have it's own animation and would have an effect on the time it takes to cast, the chance of success and the amount of magicka used.
Some possible examples:
- One style could be A casual flick of the wrist and hand it's fast and can be used with a one-handed weapon in hand but obviously cannot be as powerful and is perhaps less efficient magicka-wise.
- Another style could involve several seconds of concentrating power during which you would be vulnerable if attacked but then you could launch far more potent spells than usual.
- A third style might mean an extensive (20-30 seconds or even more) period of meditation after which you cast the spell (obviously this is the perfect kind of thing that you would do before an important battle).
These are just examples and would of course be optional because the current Morrowind casting style would be the default and new styles could be implemented through mods.
Valtur Naa's Note:
Only one style is necessary with these examples. It could be scripted to be exactly like the weapon strikes, time for "preparation" increasing power, but the release comes whenever you let off the trigger. Then, the animation could be long (maybe ten seconds or longer) with one loop at the end; or, alternately, there could be several looping animations that the engine ties to certain holding durations. And however long you hold, that affects your spell power in either a straight line or a curve.