Presence of Mind: Overpowered in Situations, Unused elsewise.
So, I played an ARAM this morning on Brand that lasted 8:35 and was 3 kills to 21. These are the stats of that game just from the Overview standpoint. What that doesn't show you is that Presence of Mind gave me over 3.4k Mana back and 100 Seconds of CD Ult refresh.
While I am suggesting a change for a Rune based upon ARAM, I rarely see PoM taken outside of ARAM due to the low kill nature of the game. What I would suggest is either lowering the amount of Mana restored, lowering the Ult CD given on kill/assist or giving it an internal CD like others have been given to help prevent someone from ulting at the start of a fight and having it back up by the end when you get 5 K/A's.