Lucia No Rupture

Started the game on Aria's banner so no option for Rupture agent. Basically wondering how valuable supports like Lucia are. Although I don't think I'll be pulling for Yixuan on a Rerun, if a new Rupture agent were to drop, would Lucia instantly BiS? Can't predict the future ofcourse, but compared to similar scenarios with other types support agents, have they still stayed BiS for their niche?