I don't think she's ever going to be 'put to rest'.
She's the Dawn character of this series. She's important, but she's not integral to the plot on a week-to-week basis and it's got people wondering why she's even there - much like they did with Dawn after S5, even when it was obvious that Buffy needed Dawn and she was never going to go anywhere, whether she was useful or not.
Skye is a very slow burner, but, then again, the show in general is a slow burner, though it's been getting better, and I think Skye's role is the type of role that can only be defined as the series goes on. She's the noob, she's new at EVERYTHING, whereas everyone else already had their roles defined, and Skye's just floating, trying to find her place and trying to be useful in a world she doesn't really understand. I think Skye will play a huge part as the season draws to a close, and it'll probably be her idea or input that saves the day for everyone, because she's that kind of character.
Personally, I don't really mind Skye. She's not my favorite character, but she's certain not my least favorite. She's the human character, the character that everyone on the outside can relate to, because she's us on the inside. And I like that.