Janna Turret Shield Update

Can we see some update for Janna shielding turrets? Her shield with any amount of AP or shield buffs still only takes one hit from any champion to get rid of. Yes, I have seen that one hit be very influential in a fight or enemy dive but its rather useless for anything but maybe defend against a few minion autos.

Ziggs can one-shot a turret with his passive and W but Janna can't defend it in a reliable way. This seems very similar to the Karma shield on minions, useless and usually just in the way unless it could be buffed. It also seems like a waste to use that cooldown on a turret without much in return.