So, can someone who already has a copy of HH say something about the contents of the scenario booklet we've heard about? Any info would be GREATLY appreciated.

They're all sieges of the palace with different restrictions. For example the 1st is a standard setup, and then the second gives the Chaos Player more freedom in troop selection and positioning.

Care to divulge something more, like, for example, the names of the scenarios, which one you find the most intriguing, challenging, etc.?

From what I recall of my perusal of the scenario booklet...

There's a scenario for first play. Pre-arranged setup, removing some of the more advanced cards from the decks.

There's another for some modest freedom in setup and unit placement.

There's one for complete control over unit deployment at the beginning.

There's one including all components in the game, including all cards. Which is supposed to be the most random.