Chem I agree with Tony, if your plants are getting direct sun, even if only for a few hours, then it isn't that shady. Longifolia and adnata which I mentioned above both grow in places where they NEVER recaive any direct sun. Adnata on a vertical cliff face in moss beneath bracken ferns and longifolia is plain weird. It grows right on the jungle floor together with aroids and other low light plants, very unusual place to find a Nep.
Your site will support quite a few other Neps, I still think bical and amp would be suitable but with some sun you can add others like albo-marginata, reinwardtiana, almost any lowland.
Cheers, fatboy.