Yes! I like the idea of HIVE interest. To encourage constant holding by individuals and not exchanges, a time component should be added to the HIVE interest. For instance, it should take X amount of time without withdrawing from the HIVE savings account to get up the the full Y percent interest rate. Moving any amount of HIVE out of the saving account resets that time. This will encourage people hold to get the full interest rate. It also makes it harder for exchanges to stake and pass that interest on to their users because presumably they would need to move HIVE out and that will constantly reset their time to get the full interest. Something like that. Just a thought.
Edit: this time component could be long, say 12-26 weeks. It would force people to really think before pulling HIVE out but if needed, they could pull it out fairly quickly.