the premise of Cybermen is scary-they take your still living brain and stick it in a robot body-that's truly disturbing. The problem is the Cybermen LOOK silly.
And unfortunately the only obvious solution is to make them look more human, but then they are pretty much Autons.
I know it's a pipe dream, but I'd love Gaiman to be Who's new showrunner. Doctor's Wife was such a love letter to the show.