This is a really sweet design! I like your slanted windows for maximal solar gain. The vent in the door is a good idea to let excess heat escape. In fact, I would put some of those above the windows too, or into the roof. How about those water tanks? Do you want to use them for thermal mass as well? Just being exposed to the winter sun would warm them up to raise the inside temperature of the greenhouse.
But please don't let my sudden brainstorm distract you from your plans. I'm excited to see the development of this awesome project. Oh, btw, I love your cad renditions. It makes it all so easy to visualize.