Many thanks.
I've been kicking around what I want to coat it with after I get it built. The last one I made, I covered the whole thing with duct tape, and then hardened it with fiberglass resin. When the resin seeped into the duct tape, it made the tape crinkle and bubble, and formed a really cool-looking texture that I really liked---but it was also a wee bit heavy.
I'm thinking this time I may go instead with a thin layer of silicone (probably plain old bathroom caulking) to make a sort of shiny skinlike texture.
And if I feel ambitious I may do one of each.