I'm not sure about the whole heat issue, but I do know that on the side that I had the heat mat for my Emperor, if I turn it on, any Pothos root almost immediately burns, and then five more grow from that.
As for the plant choice, I think pothos would be a great choice because they love that humidity. Pothos vines come from the rainforests. Also, they don't need much light at all, and get very large.
Another plant I would recommend is a philodendron. They also have the same qualities that pothos vines have, but they don't grow as tall. They do grow faster, however.
Both plants are currently battling it out in the empty Emperor enclosure. Pothos vines will grow very tall and throw their roots into any open space they can, and then grow the leaves. With the philodendrons, they have shorter "roots", but grow like five at a time, and will prevent all light from reaching the areas below. Both are also in straight Eco earth with nothing else and do fine without any fertilizer of any sort.