Power plays benefit the sides that attack,not just in batting,some sides don't even go after the bowling in the 20 overs they just push it around.
The aussies proved you can use it in the bowling as well.
20/20 has helped develop one day cricket as well.
Reason australia is so far ahead is they have embraced 20/20 and the power plays some countries have not.
The supersub tended to = things up with the supersub as you could play an extra bowler.