I like Billie Eilish, but she's not a headliner for me. I saw her on the 2nd stage last time I went and it was a little dull to say the least. She's an album artist, something you throw on some headphones and it sounds great, doesn't work for me live.
Kendrick will put on an incredible show however (even though it's not my thing)
Macca, well he's just legendary, even if he's old and by many people's accounts 'past it' - But I think it'll be quite a moment... I mean, it's Paul McCartney!
Diana Ross in the legends slot too. Great!
Even if you don't fancy any of the above, there are tons of other great artists playing.