U.R.F Galio Exploit

So recently after playing an u.r.f game, the enemy team had picked Galio. his build was the following. Spirit visage, and thornmail. That was it. He managed to have 300+ armor 10 minutes into the game. after sitting for a few minutes just healing off our auto attacks and being unstoppable he backed to pick up a banshees veil and frozen heart. He then just sat in between our two nexus turrets literally healing off both at once. his team proceeded to push them down and by the end of the tanking, he was full health. Please riot, i understand this is part of his kit, but there has to be some sort of balance toward that.