I am relieved to report that King of Terror is the best Doctor Who book I have read by Keith Topping. This is faint praise, because I really did not like either Byzantium! or Ghost Ship. The prose style seemed a bit more under control here, though it still isn't a very good book: lots of gratuitous violence, rather improbable scenes not quite involving sex (separately) for Tegan and Turlough, and peculiar unexplained irrelevancies like the Doctor's dislike of the CIA, and Tegan's future marriage to the rock-star son of Ian and Barbara. One to skip.
October Books 13) Imperial Moon, by Christopher Bulis
This is a different matter. Bulis has made some effort to get to grips with the Victorian boys' adventure genre, and here we have a British expedition landing on the Moon in 1878, seen off by the Queen herself (and thus inspiring my question about steampunk the other day). There's also a slightly contrived but not too horrible subplot of the Tardis crew crossing their own timeline, and Bulis even finds two useful things for Kamelion to do (which is two more than ever happened on television). I didn't quite swallow the ultimate reveal about the aliens or the Doctor's trigger-happy way of dealing with the problem, but it is at least a decent effort.
October Books 14) Superior Beings, by Nick Walters
I think this is my first book by Walters, whose Wikipedia page describes him as the author of many Doctor Who novels (where "many" apparently means "four"). He has done rather well on characterising Peri as young, vulnerable, and actually interested in botany; she is pursued as sexual prey by one non-human and then as literal prey by the nasties when they show up. The nasties are engaged on a mad religious quest as well as killing and eating passers-by, and the Doctor inevitably has to put a stop to it. It is a decent enough novel but I could have survived without quite so many scenes of brutal dismemberment, and also there was the odd annoying editorial slip.
I wouldn't really recommend any of these three to someone other than a Doctor Who completist, and would not really recommend King of Terror to anyone at all.