It'd be nice to have the nature of the world be fantastic and acknowledge that there's fantastic stuff that effects magic, be it material, technique of meta physics.
For example:
Witchbane Woad
This paste of willow, wysteria and mandragora pulp can be applied to the body to provide a bonus to saves vs effects caused by arcane spells.
Meditation on the Hidden Ways
Each morning, one may spend an hour meditating with a tea of certain herbs and talismans. Doing so allows you to become aware of any magical effect within 10ft of you. As an action, you may focus on a square to discern what objects or creatures within that square is generating a magical effect. IF you are trained in Arcana, you can discern the nature of that magic as normal with the skill.
Sunderweave Technique
By combining the heightened awareness of the Meditation on Hidden Ways, the warrior can make an attack against a magical effect on a creature or object. Make an attack against the target. On a hit, treat this as dispel magic. If you can discern what effects are on the target, you may choose which to dispel. If you are not, you dispel an effect at random.