User blog comment:C4bal/Support: Lydia, the earthen Ambassador FANMADE/@comment-1330314-20121221122900/@comment-1330314-20121221233810

Actually, 's shield is about the same 's, as the maximum base shielding is 360 while the scaling is still at 70% AP. The former can be applied to multiple targets, the latter gives immunity to most CC and yours gives increased attack speed, so you should still downscale the AP ratio.

Regarding your ult: most ultimates and powerful spells last for a very short amount of time. Not counting the exceptions (such as 's ult, which is basically a fourth basic ability), ults are supposed to be huge yet momentary increases in power that can turn the course of battle. Yours is good enough a steroid to warrant a larger cooldown than the one you're giving to Lydia.

If you want another title, I'd suggest "Lydia, the Earthmaiden", or "Lydia, the Earth Mother". In the end, it depends on the background you want to give her.