I'm pretty sure they lie more with him being actually unkillable in a 5v5 situation and coming out with full hp afterwards. His CC and stick are annoying enough to deal with,especially when he builds 
, does he really need to heal for 700~ hp every 3 seconds in a teamfight?
he heals based on his hp and it has a cooldown that is a lot longer then 3 seconds
Sap Magic STATIC COOLDOWN: 30 / 25 / 20 Sap Magic INNATE: Each time Maokai casts an ability or is struck by an enemy's ability, Sap Magic's cooldown is reduced by 4 seconds. Sap Magic 2 Periodically Maokai's next basic attack, after a 0.25-seconds delay, against a non-structure heals him for 5 - 65 (based on level) (+ 6% - 13% (based on level) maximum health). Sap Magic will not heal him if he's above 95% maximum health.
2ndly dont need righteous glory at all on maokai , yes its nice but not needed
