Potentially, due to sub availability, she'll be a great balance between both stall AND burst.
Lead with her, have 2 max skilled ecchis, and 2 kushis (yeah i know, i wanna poop them too) and you can have reliable x16 at will, delayed enemies, and 75% reduction to take hits a double luci team could. And while your x16 eont be up every turn, itll be up frequently, and you can simply prepare for those turns.
Having a skilled siren is also good simply for cd spamming.
Also, she'll prob be one of the best challenge mode leads since you CAN double kooshy easily in that case.