Two things I'd like to add.
In the two years of the Games, there has always been the hill run. So include some hill sprints, including the rare downhill run once in a while, and some track work.
I'd say stick to the power-biased, heavy metcons as you are planning on doing. I think it would be better to train more than one of those in a day rather than start doing longer metcons one-at-a-time. Due to the scope of the Games, I believe that they will stick to heavier metcons--this both weeds out the weaker folks, makes the event easier to run, and is more exciting for the spectators.
Note that none of the top 5 times in ANY event for the women last year went over 7 minutes, and nearly all of those times were under 5 minutes
. While the events may change, I doubt the times (in terms of lengths of events) will.