The problem with Doctor Who is that there aren't that many memorable ships or settings. The minifigures and the TARDIS would be the real highlight. LEGO could do a Dalek saucer, etc. and some interesting scene recreations, but the real stars would be the figures. At least it has more possibilities than Star Trek. Also, Doctor Who LEGO would probably sell great in the UK, but I'm not sure it has enough exposure elsewhere in the world.