Well, I would not worry about the humidity if you use live plants (which stabilizes the humidity), sphagnum moss (great to maintain moisture) and a misting system. I live in the northern parts of Sweden, so the humidity is really low in the winter here as well. However, I'm having a hard time to keep the humidity down even without anything covering the tank
These are however changes that you easily adress later on, if you find the humidity too low or too high.