Any plans for time in a bottle?

Zilean's new passive is an exciting change for the time mage and one that is a good step in the right direction. However, at the moment it feels like you are just giving a minion or two worth of XP every two minutes. Are there any plans to buff part of his passive in the future? Whether it be the cooldown, the XP gain or something to make it feel more impactful on the game rather than "Here, have a free minion!"