I love both, but my Warden is the type who would insist on staying behind. After all, she's a Paragon and all-around badass. What better way to go than in an epic battle with a giant demon? She might even win. She killed the Archdemon, multiple High Dragons, a Varterral and the Mother. I can see her coming out of the Fade later, covered in demon spirit goo, being like "time to get a bath and then royally drunk".
Also, Leliana can probably handle losing her. She's hardened and I'm making her Divine.
Anders wouldn't survive losing Hawke and I can't ever make my bird mage suffer.