Spell incantations are still being shouted VERY loudly. While this is fitting for an offensive spell, shouting like you want to rip someone to shreds just to create a Light or cast Guidance in a dungeon is not. There are many situations where discretion would be much more sensible than shouting at the top of your lungs. When Shadowheart shouts Guidance just to disarm a trap, it feels like enemies should rush in to see what the ruckus is about.
A more dynamic approach where some spells could be almost whispered would be much better from a narrative and stylistic point of view. It would also be a great way to give spells different kind of character. E.g. Illusions could be more whispery echoy mysterious, Enchantments could be soft and alluring, Abjurations could be steadfast monotonous speech, Conjuration could be calls that echo, Necromancy could have some spirits whispering in the background and Evocation could be the brash shouting we now have for basically everything.
And whispering really loudly can be great for a dramatic effect. ,-)
