You know, I just realized part of what I really like about how Echoes looks so far is the sense of actually exploring a new alien world with Samus. Metroid has always been about lonely exploration, but it also has re-treaded itself a great deal - returning to Zebes often, sticking with similiar ship/station/mechanical corridor zones, and even Talon IV in Metroid Prime seemed for the most part to try and bring Super Metroid into 3D so it aped those kinds of stages. Though the Chozo Ruins did feel fresh to me and pretty epic.
But Echoes from what has been seen, really feels like Samus actually exploring the rest of the universe finally, even if Space Pirates and Metroids are involved somehow. Same goes for the Ing and majorly new styles of enemies and monsters.