I find all of the effects to be significantly UP and not at all worth giving up a shield tbh.
Not all of them are that UP.
Phase shield and wings aren't too bad to give up when they are about to expire...
same with boneshield.
The grav one is definitely worth it imo. It would make "its a trap" doable as a duo... that could get ugly (put this + grav pull on a titan and watch the enemy weep)
The
one gives gaurd, which could be quite devastating if played correctly (for instance, if a heavy hitter gets AM'ed you now have a powerful healer. Also works well to let a heavy hitter stay occupied in case of SoSac)
Still, I see bogtro's point some of these shields are quite expensive. I'd say the creature should gain a stat bump (hp, and maybe att) as well as the ability. Maybe make the extra hp relative to the cost of the shield.