One thing that has been regularly talked about during our risk games is when the attacker rolls 2-3 dice and whether the defender should roll one or two dice. In the last section of the book there is a section on dice probability which is great, however if the attacker rolls 4 and 3, what are the odds of destroying 2 armies with 2 dice? How much risk is involved AFTER the attacker has rolled?
It might be a good suggestion to give the odds with a caption for each possible 2 number outcome (i.e. 5 & 3, 6 & 2 etc) and the odds of the defender winning. I once rolled 3 sixes and with my naive friends ignorance of dice odds, rolled 2 dice and scored both sixes - I'd like to know the odds of that!