Glassheart is amazing. I don't really like the order of the songs but with this order it improves a lot:
1- Come Alive
2- I to You
3- Trouble
4- Un Love Me
5- Lovebird
6- Fireflies
7- Shake You Up
8- When It Hurts
9- Glassheart
10- Sugar
11- Favorite Scar
12- Stop the Clocks
13- Colorblind
14- Fingerprint
15- Collide
But I love pretty much every single song of all four (five with the Christmas one) albums. She's just amazing.
It's a damn shame the way the Glassheart era was handled. Come Alive would've been the perfect lead single and then Glassheart (title track) released afterwards.