I have 10 etheric lights on my Titan alone and no armor or weapons left to upgrade. I'm afraid they're just going to pile up in my vault like the thousands of ascendant shards I had. However, I was able to trade those in for roughly 1500 motes of light. Since this is the current-gen currency I was thinking we should repurpose them for something or at least make them exchangeable. I know not too many people have this problem right now, but trust me it is coming fast.