What stops you from not using the feather cape and just wearing what you want, use mead if needed? I wouldn't call it OP--you're most of the way through the game now, there should be a power creep leading to the final boss(es). And it won't help you in the Ashlands so that's not really an issue, it'll primarily be for mountain hopping (frost cave hunting) and Deep North. Seems fine to me.