For those stressed out about this new "taxes" or "fee" you don't really have to worry since just like the 5% taxes on selling, you can always rent your card at your desired price +1DEC and that will be like nothing changed at all for those renting cards while it will help burring DEC.
This will also make those 0.01DEC cards get rented for 1.01DEC or people will stop listing those but I doubt it will be that much impact on the renting market for the users.
Of course taxes implementation is always something that scare people but if it's good for the servers and if it help the DEC peg project overtime, it should be positive.
So unless there is something else I don't see right now, this seems like good implementation.