Can Zilean's double-Warp get some love?
Even something super simple like "Reapplications of Time Wrap will extend the duration, rather than refresh it", so I don't feel bad wasting 0.1 second of the duration - plus it allows me to stack it on someone who I know is going to be out of range for the second cast.
If you wanted to go further and give it an empowerment - something that's still relatively simple could be "Reapplications of Time Warp will extend the duration and, if an ally, grant them immunity to slowing effects for 2.5 seconds." But you know... just if you want to.