Now that the final map is here, here's my final ranking:

>Survival gameplay
Reckoning>The Tomb>Terminus>Shattered Veil>Liberty Falls>Citadelle

>Atmosphere and soundtrack
Terminus>Reckoning>The Tomb>Citadelle>Shattered Veil>Liberty Falls

>Easter egg
Terminus>Reckoning>Shattered Veil>Citadelle>Liberty Falls>The Tomb

Overall winner: Terminus
But Reckoning is pretty solid on its own despite the awful ending.