I remember the manual/strategy guide for the original Age of Wonders... I think they gave it out as a pre-order bonus at the last minute or something because I remember getting it rather unexpectedly. That thing was nice and think, with pretty much everything you wanted to know about every unit.
No, it seems it was the regular manual, I have it too. I remembered it being good but, reading your post, I just took it from the shelf to take a look.
WOW!!
Let's see:
- 186 pages
- dozens of screenshots to illustrate the text
- 11 pages just TO EXPLAIN THE TUTORIAL! And every move described in detail (Exemple quote: "If you wish to deselect a unit from a party, simply left-click on the small movement icon below the unit's picture.").
- chapters covering campaign, interface, combat, diplomacy. Did I say "interface"? Yeah, those guys knew their job and wouldn't tell us that "everybody playing strategy games should be able to understand the interface" like I read somewhere around here (not from Stardock, I must add!)
- the complete list of races, units, spells. The list of hotkeys. It even has a two-page INDEX at the end!! (in addition to the two-page Table of Contents at the beginning)
- and there is some lore too.
A model! 
Same can be said of the Alpha Centauri manual (200 pages). Just by reading it, you knew the game would be an amazing experience.
If Stardock wants to cut some from their manual, they should put some very detailed and explicative tutorial.