Hi, this is Kimberly from landscape-solutions-for-you. Thank you so much for asking the question on shade plants for your zone six. I am sorry for the delay in responding, but I have just finished up an SBI conference.
Besides the plants you mentioned, Pieris Japonica, Camellia, Aucuba, and ferns will work well. The Robin Holly and Nellie Stevens Holly should work in full shade. My crew and I have used these two Holly specimens in full shade and haven't had a problem with them growing in zone seven. With your large pine trees, pines produce acid in the ground. Some Camellias will get tall, which will produce the privacy you are looking for. Cleyera is also a good specimen for shade.
I hope this has helped some and let us know how you make out. Thanks again and feel free anytime to ask a question or share your ideas with other visitors. Have a great day!
Kimberly