You could take away their miscellaneous item slots, thereby denying them the flying ship and carpet. Maybe give them a hat slot (or some other slot) instead to balance it out? Maybe add a summon allies of a hama dryad or some other nature creature?
Keeping Faery Trod while disallowing movement via items is key, I think. The routing problem is less severe, in my opinion.
In my current game, Turin is rampaging around with a large Treelord led army on a flying ship, so I definately feel the pain
