Kind of feel since album 1 & 2 Foals have struggled album wise. 3 onwards each album has had 3-4 big hitters then a big chunk of filler. They can definitely pull together a solid setlist but certainly IMO the quality of the output started high and has been slowly going backwards.
If anything they are probably now moving further away from headlining than getting closer. Unless there next album is gonna be absolutely solid I think they would be better of doing an Antidotes tour or greatest hits to stop the backwards slide.
Welcome! You'll love the festival. Some good speculations there, but I can't share your hopes for Joanna Newsom. Not only would it be an unprecedented third EotR headline slot, she has history of making all the other stages shut down while she's on, so those of us who aren't fans don't even have the option of checking out something else. It's Newsom or nothing. And personally, I would rather burn my own pubes off with a blowtorch.