Its a Target Novellisation, give it a break.
A very simple tale of goodies versus baddies in a very black and white world. But the Doctor, Steven and Vicki come across well and it occupies a couple of hours easily enough. ( )

http://nhw.livejournal.com/871029.html

Galaxy Four was the first story from the third season, shown in 1966 (odd to think of it as the Classic Who equivalent of Smith and Jones). It's the only one from that year I haven't yet seen/heard, but I got the novel for free yesterday with the SFX Doctor Who special and read it pretty quickly. It's actually rather good, up there with the average Missing Adventure of the Virgin series. with Emms (who wrote nothing else for Doctor Who) letting us inside the mind of the Doctor very convincingly, and also attempting to flesh out his rather one-dimensional villain, Maaga, leader of the female Drahvin warriors. Must try and catch up with the actual series now, though I have a suspicion this may be one of the cases where the novel is better than the story.

https://fromtheheartofeurope.eu/galaxy-four-the-newish-dvd/

Coming back to it fifteen years on, I remain favourably impressed. Emms was clearly a fan, and fills out the narrative not only with scenes that he would have liked to include in the actual show, but also with subsequent Who lore – most of the references to the TARDIS crew being from Earth are removed, and there are several mentions of the Doctor having two hearts, which of course wouldn’t become TV canon for another five years. We also find out that the Rills don’t share our concept of time. It’s well done. ( )