I meant to say it's only important to see VFX for Mage Armor and Arcane Ward in combat and even there I'd prefer a much more subtle approach or no VFX at all for those two.
You need to leave room for VFX so that more powerful short term protections and effects like Blur or Globe of Invulnerability can look cool and be easily recognized. And that multiple active spells don't turn the character into an ugly mess.
