Preface: Imagine me being contrary!
Personally, I think <R11> is the single best rule in the manual. This creates a challenge we haven't really seen before (Aim High had a little wiggle room) that I believe will create a plethora of designs and functions. This forces teams to create elegant and efficient designs, and pushes the inventive envelope.
Think of 2007. That game was the antithesis of 2009 - teams created huge, delicate manipulators that were protected (overbearingly so - ?) by the rules. Most of the robots there were carbon copies of each other, with only a few exceptions.
Every offseason, FIRST participants clamor for a new game, one with new and distinct challenges, the likes of which they have not seen. Well, here it is! (At least they're not making us climb Regolith ramps!

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