Leona is in a strange (but much better) state

Leona is my main, and since her buff (which i felt she needed despite my friends saying she didn't) i have seen MUCH more success with her. one issue i have however is that after around 30-35 mins, her 1.5 second stun is hardly enough to make a difference when the enemy has the HP to not be bursted and the enemy tanks/healers can heal much better at the late point in the game. i do NOT believe it NEEDS to be buffed since a good Leona can still do good cc in these late fights, but no where near what another tank support could do. Many of the unexpected tank supports like Sion and nautilus can out do Leona very easily as both a tank, dmg dealer, and CC all at once. it is for this reason that i believe Leona could use a nice Q stun scaling buff, However, i think it should be a unique Leona mechanic, i dont want it to go out of control, but if it were to scale the stun duration with her AP (her ratios being bad anyway) it could add for the option to lose some tankiness and survivability, in exchange for the ability to provide more CC in the later fight. Another idea is to give her passive AP scaling, to grant another option to her build pathing.

Pls post your oppinions and whether you agree or disagree.