If you're going to do a set of character pieces on Doctor Who villains, Davros is an obvious choice. A man willing to destroy his own race is an obvious candidate for a story that dives into his psyche. And Lance does a phenomenal job here.

A theme across this trilogy is that each story is telling two stories: one in the present, with the Doctor thwarting the latest evil scheme, and one in the past, describing the villain's origin. This is partially guesswork on my part, but I assume Master follows the same formula. And, if the trend holds true, then the present section of each story also prominently features the villain going through some sort of mental break which ends with them reaffirming who they know themselves to be.
Unlike the other entries in this trilogy, Davros also has an extra job to do, as there are stories with him set after this (again, assuming Master doesn't try to set up the TV movie), so a good chunk of the story is also devoted to laying tracks to set up Revelation of the Daleks, which I now have to rewatch.
Everything in this story comes together. The ties between capitalism and fascism, the hero worship in modern societies toward monsters of the past, the use of propaganda... just an incredible story which gets to the heart of everything.

It's no secret that Omega is my favorite Doctor Who villain. I love the angst and the lore and the anger and the irony and all of the juicy, juicy drama tied up with him. The Three Doctors is one of my top stories in the entire show. Arc of Infinity has Omega. Time's Crucible, in all it does, finds time to stick Omega in there. The Infinity Doctors- part of a previous anniversary- gets my vote of quality in large part due to the excellent AU Omega content. And this story is no different. It plays further into Omega's madness and backstory than ever before. It presents all the possible ways that Omega's history could've played out, and it tells us a little of the Gallifreyans before Omega and Rassilon came to power.

All of the characters in this are excellent, and everything comes together in shocking and unexpected ways. I can highly recommend this audio to anyone looking for a good Big Finish to start with. It's untied to any audio story arcs going on, and it's free on Spotify, and it's completely excellent.
And it is a crime that Nev Fountain has written so little else.