I actually think it probably would have helped to be less moody, just because in Who "moody" tends to mean "dark and poorly lit so it's SPOOKY," and while I think it's necessary to do that in an ep devoted to shadows, the more shadows there are the more difficult it is to keep track of them (and they were having trouble keeping track of the shadows that were there already).

I hope we see Lee McAvoy again! After all, Martha's doctor boyfriend Tom made an (offscreen) return...though it helped that he was from the 21st century and from Earth. And given that I'm worried they're going to kill Donna off at the end of the season, I'm not imagining she's gonna get too much of a happy ending with Lee. :(