Another thought - Perhaps trim the skins into a circle... but I think it would be fine as long as you bake and cool the skins first, w/o the filling. Also like the presentation of using two skins to form a star.
Here is another way to go, I really like. The herbs are pressed into bread... wonder if it can be pressed onto the skins or sprinkled w parm.
P.S. The mushroom/brie filling looks very good, as does the sweet potato filling. Hope I helped some and maybe there are some ideas you might want to experiment with. Again, your dish looks delish.