This story has some interesting themes: politics, conservatism, change and tradition. It didn't particularly have a moral story in regards to these themes, it just sort of used them and discussed the pros and cons of these ideas, which was really interesting! Although the Doctor is certainly fighting to stop Hepesh, I get the feeling during his death scene that it's left for the viewer to decide who was right and who was wrong; should traditions and heritage be preserved or should we embrace change? This serial doesn't give us a 100% yes or no. I really like that.
The costumes in this story were great, even if the voice acting for Alpha Centauri certainly wasn't... Although I'm surprised that my suspension of disbelief didn't break and still managed to resist its incredible ridiculousness.
It's interesting that the Ice Warriors are in this story but not actually the villains; all throughout the story there was mystery about whether they were the ones behind the mischief or not. I think typically in Classic stories, when something is alluded to early in the story like that, it does indeed happen as you suspect it. It's interesting then that in the story they make the viewer think it's the Ice Warriors behind it all but in actual fact they're just bystanders and any dubious activity on their behalf is simply to protect themselves and the Federation. Although I'd have liked to have seen the Ice Warriors as the villains, I'm glad that they went for something different and more interesting with this.
Loved the action in this story, even if there isn't nearly as much as normal. Once again, the Doctor gets to show off some moves! It's quite enjoyable seeing the Doctor fight because unlike with other heroes, you know he's not fighting to injure or to kill, he's trying to stop the fight with the least damage possible. So seeing the Doctor fight is always something refreshing. The fight scene between the King's men and Hepesh's men in the throne room is also fun.
I too noticed the Venusian lullaby was to the tune of 'God Rest Ye Merry Gentlemen'. That was awesome! Pertwee pulled it off really well, too, it was genuinely soothing, and definitely catchy! "Harroon! Harroon! Harroon!"
All in all, this was an enjoyable story. The only cons were that it wasn't overly exciting and Alpha Centauri's voice could grind one's gears at times. Other than that, it's quite an interesting story and certainly an enjoyable one. 3 stars from me.