That's how the hatches on my Arluk I, and I believe most of the other Necky boats, are done. They do have fiberglass lids to go over the neoprene, which are held down by webbing. I'm not sure I would like just the uncovered neoprene as it might be a little too susceptible to being blown out by a dumping wave.

You can easily make the neoprene covers yourself. They're just scaled down spray skirts without the hole. There is a good description of making a spray skirt on John Sweet's web site.

: My cunning plan next time is to make a mini cockpit hatch (lip + rim just
: like your cockpit) and get a neoprene sprayskirt (like a shower cap)
: covering. It would look a bit ugly, but my bet is that it would be pretty
: simple to make and pretty waterproof. This is from my experience of
: splashing around the place and comparing and contrasting the amount of
: water inside my cockpit compared to my aft hatch and making allowances for
: water brought on board by tootsies.