Idea for a Taric rework

So I was just thinking about how to stay true to Tarics theme (crystal/paladin) while giving him a kit that works together and has a niche. I'll give it to you, explain sample builds, and then explain the reasoning and possible roles

Passive(refraction): 30/40/50 percent of all non physical damage Taric takes is converted into physical damage

Q(harden):Taric shields himself for (40/45/50/55/60 +20ap + 30% armor). This shield does not wear off and can stack with other shields from Taric. The shield can be used on allies , with half the ratio and base (14/13/12/11/10 second cool down, 50/60/70/80/90 mana cost)

W(shatter): Taric shatters the current shield on All nearby allies and him, dealing 1 magic damage per shield health to nearby enemies in a 350 radius and slowing them by (20/25/30/35/40) percent for 2 seconds (14/13/12/11/10 second cool down, 40/45/50/55/60 mana cost)

E(crystallize): Taric briefly stuns an enemy within 500 range for (.6/.7/.8/.9/1) seconds. If an enemy champion takes damage from shatter, the cooldown is refreshed (20/19/18/17/16 cool down, 80/85/90/95/100 mana cost)

R(imbue): passively, grants Taric 20 percent bonus armor, spitting out half of that to allies within 650 range (they gain 10 percent of Tarics bonus armor). Taric can activate this spell to slam down on the ground with his hammer, dealing (100/175/250 +40% ap +40% armor) magic damage to enemies within a 600 range and granting (20/25/30) percent movement and attack speed to nearby allies for (4/4.5/5) seconds. The passive does not work while Tarics ult is on cool down (60 second cool down)

Important stats: Armor/mana/cooldown reduction

Sample build(top): Frozen heart/ ninja Tabi/ righteous glory/sunfire cape/randuins omen/(mikaels/locket)

Sample build(support): sightstone/face of the mountain/ninjas/frozen heart/locket/randuins

Ideas: Taric is a support (he plays like one either top or support) who must choose between offensive or defensive play, each side powerful but lacking. He can continue to stack a shield on an ally in lane, but forgoes literally all damage in lane and some of his cc. he can also use shatter liberally to harass and chain stun, but loses the safety. Same for his ult. The armor aura I'm proves the power of his shield and makes him deceptively hard to kill due to his passive, but forgoes damage and the stats his ult provides, and he also loses both while it is on cooldown. While he doesn't have the tools to dominate top, he could play a supportive top role like lulu, while using his shield and stun to remain safe(imagine juggermaw with Taric top and lulu mid). In a support role he would almost certainly start q, and would probably use the shield on the jungler, giving him a super easy first clear. After that he would shield as often as possible (him to immediately deal damage and chain stun with w and e) and try to build up a shield on his adc (note mana and cooldown reduction are recommended). Ive never designed a champ before but I was just wondering what you guys thought.