The Tenth Planet is a very mediocre sort of story. The Cyberman designs are really fun, better than the more recent more robotic versions just by virtue of how it reminds you they were human once, too, but then it doesn't really do much interesting with them other than an "Oh no! The enemy is invading the world again!" plot. The side characters are okay but nothing special, so the plot is mostly carried by the main cast, but even then Polly as the single female character in the whole serial gets sidelined as The Screamer every time the Cybermen enter.

But perhaps more than any of that, I'm going to miss the First Doctor :(