It´s not worse. In fact it´s better. Doesn´t make it OP by any extent, but it is quite the double resistance item. Offers about the same amount of resistances than ZZ'Rot and GA do, having just 5 to 15 less than either, while being cheaper. On Renekton, it´s bought for the resistances, not the shield itself. That being said, they could reduce its resistances and increase the shield if it eventually becomes a problem. And since it´s League, eventually every item becomes a problem once or twice.
As for Redemption....it´s what every tanky frontline or squishy backline support want, with a few exceptions to that. More health, faster regens and CDR.
WHILE being able to use its active when dead. Time and time again i see teamfights get flipped around because of a single well timed Redemption active. And it takes the targets' level into consideration, rather than the user's level.
Higher level people get healed more, regardless of the level whoever used it is. Since the support is expected to be at least 1, 2, on some cases even three levels below the ADC, changing that to consider the user's level rather than the targets' health, reducing the base health and upping the per level heal by 5 should solve the issue. It´ll be 25 HP worth of more heal at level 18(515 if the base heal changes to 65 and per level to 25, against 490 with 130 base and 20 per level) though. We won´t know what Riot will do to it when they get back from holidays.