Shame that when they were doing a lot of Who novels, during the wilderness years, that we never got a spin off UNIT series. I think they did one book featuring UNIT saving the earth without the Doctor and that was it.
Big Finish tried a UNIT series, but aside from a couple episodes where the Brig guest starred it was only okay.
Have you seen the SJA episodes "Death of the Doctor" with Matt Smith and Katy Manning? Lots of fast paced action and some nice moments ackonwledging the original series' history.I recommend them as there are some lovely moments of flashbacks (via old series clips) tying the classic and modern eras together.