Personally, for the J's I much prefer all of the different versions in the un-shrouded and un-skirted state.
For the cone, cast aluminum of that size and shape would still weigh quite a bit. If they could create an aluminum inner frame and shroud in thin aluminum sheet, it would be much lighter, but at the size still difficult to maintain. I would think for the skirting there are many options they could use to get the look, but be easy to remove for maintenance.
