[DrPraetorious]

The cavalry in this weight range don't generally pay for barding - none of the amazons do, for example, including the onyx maiden who has almost entirely the same equipment (she costs 1 RP less since she doesn't have a javelin.)

Beyond that, given the speed of the Fey horses, it seems pretty obvious they are not wearing barding. It'd be nice if there was some way for enemy units to exploit a lack of barding on your horses.

maybe - when a mounted unit is repelled by a reach weapon, it has to resist a big pile of stun damage using the barding? Then the barding would need to be specified and have a rating, this is getting off topic anyway.

Now, if it were needful to raise the resource cost of Vans (which I don't think it is, but for the sake of argument), we could just have them wear light-weight, magical barding, which seems common enough in Vanheim, and would presumably have the same resource cost as whatever barding slightly heavier cavalry usually get.