As I have hit an impasse as to what Psychic Pokemon I wish to get a Mega Stone for, I shall leave it up to the public will. My choices are between an Alakazam and a Metagross.

Now, while this is already a hard decision, it becomes doubly as hard due to both Pokemon being channeling partners and thus Mega Evolution resulting in increased abilities. With Mega Alakazam, there will be an even more empowered super mode for Reno that will improve all of his other abilites to a certain degree and there will be an even more enhanced version of the teleportation that he displayed previously in the Kalos arc.

As for Metagross, it will gift Reno an even more improved Psychic powered arsenal of Psychic impact moves for punches and kicks and an even more enhanced analytical and predictive ability to better contend with whatever lay in front of him.