Fiona Apple (Saw her a few months ago and she would be a great act to close the outdoor)
The Cardigans (With their recent reunion minus Peter on guitar they would be a nice Chella Reunion)
Weezer Blue/Pinkerton with Matt Sharp (This would be a reunion, and would be nice to hear Weezer play the first two albums with the original line-up)
Beach House / XX / Griz Bear (Repeat Chella)
Ben Folds Five (I don't think the new album is that great, but they would put a fine show on)
Armin Van Burren / Deadmau5 (Mainstream, garbage, whatever you want to call it. The fact is we know one or two big name EDM acts will be booked to close out the main stage, so may as well request tolerable big EDM acts. I would see these two artists any day over the likes of David Guetta, Skrillex, or Avicii.
Anyways, this is just my humble opinion on some artists for this year's festival.