0patience:Your tower is very similar to mine. The fan is a good idea. I had to put one at the bottom of mine, because the humidity was higher at the bottom, than the top. You may want to consider putting 3 hygrometers in it. One at the bottom, one in the middle and one at the top.
And double check the hygrometer that is in the top. Mine was off by 10%.
And if it came with an electronic humidifier, you may want to consider removing the foam and putting beads in it. I hate foam, so I opened my Hydra humidifier and replaced the foam with beads.
Just my opinion, for what it's worth. Which isn't much. LOL!