I think so, too. While predictable, Sara dying heroically would have given Laurel a believable motivation to pick up the BC mantle and fight on in her name, but it seems the writers were smart enough to realize that it also would have created a big backlash on the internet - so they gave Sara a faux happy ending by sending her back to the killer cult. And it seems to have worked in a way. There may be some negative feedback in comment sections when the issue of Laurel turning into BC comes up, but some of the boards I've been reading have been rather quiet on that front because a lot of Sara fans seem more relieved that she made it out of the season alive - even if the show might end up turning her into something most fans won't recognize.