In light of all the "why should I play Garen when we have Darius" threads, Morello has dropped off a little gift from the "possible buffs in the near future" fairy:
...we're talking about ways to improve Garen 
We want to actually keep his toolset narrow, not expand it, and just make him better at it. Garen brings only two primary things - damage and tankiness - he should be good at those. official forums.