Retarget every 6 hours
5 minute block target time
^ Both largely irrelevant because... Block reward will be based on the amount of time passed since last block found. This will accomplish the following:
* DDOSing pools to decrease difficulty will accomplish absoluetly nothing
* Discourage pool/coin hopping
* Provide incentive to continue mining even when nethashrate goes down (i.e. feathercoin)
No... Just no. Stop it.