When someone uses fireborn to come back from death the person should only be alive as long as radiance is active or if they take enough damage to die before radiance ends because that's what brought them back. For all the people that are going to say I'm just mad about crucible I got this idea when the game first came out and my raid friends were doing the vault. Or maybe a possibility of there being an exotic that made fireborn not let you down again when radiance is over for people that need that extra life