I'd be fine if it applies to physical damage raid-wides. Having low armor and rely on the rest of the party for physical damage mit.
Also, which ranged phys lacks party mit? I agree that nature's minne isn't always useful but dismantle? curing waltz? improv? party-wide 10% mit that last 5 seconds longer than addle?
I think red mage lacks personal mit. Something on par with second wind or the other personal shields that SMN/BLM have. Vercure is just a flat-out loss of >300 potency. If you match the times second wind gets cast in a fight, you'd be losing massively.