I personally would've killed the fuck out of Chloe, I didn't like her that much myself (though this episode did a lot for her character, I think), but I felt like it was much more consistent with the narrative to spare her and let Arcadia Bay get wrecked; it would feel like a waste for all the horrible traumatic shit Max had to go through this week to have her end up dying anyways. And I'm a sucker for "Consequences be damned, I'm going to save what I have that's right in front of me" stories.
But talking to my friend about it, she raised the point that it doesn't matter if Chloe ends up dead, the story and Max getting her powers is more about Max's catharsis. Without them, she would've just ended up dead, but now she got to spend a week with her old friend, to make ammends, and to (optionally) fall in love.