To The Slaughter, by Steve Cole
Penultimate book in the Eight Doctor Adventures range of novels, written (as the author explains in an afterword) to explain away a minor continuity error in Revenge of the Cybermen, but actually quite successful in its own terms as a story of grand redesign of parts of the Solar System for ostensibly aesthetic purposes that gets hijacked by several different groups with their own agendas, and a vehicle for the somewhat obscure companion Trix McMillan. Although the tone of the book is comedic for most of the story, Cole does manage to make the chaos and carnage wrought on the worlds he has created come across as really mattering - TV Who (both Old and New) sometimes seems to have a reset button after every alien invasion of Earth; it reminded me that he is one of the better Who writers - he hasn't done a Who novel since Sting of the Zygons in 2007, but has done several rather good Big Finish plays (as well as other work, of course).