I would be quite happy with a 3D third-person Metroid again so long as the world has the intricacy of Prime rather than the essentially flat map of Other M, especially after playing Bayonetta 2 with the immensely satisfying Samus costume (complete with bomb jumps and screw attacks), which outstripped not only Other M but also the standard Bayonetta experience (the morph ball was much tighter to control than the panther transformation). I actually thought Other M had the right conceptual idea of how to make 3D Metroid capture the agility of the 2D games, but the environment design and control scheme just weren't there to make it work. I hope this direction isn't abandoned completely, though there might be some fundamental restrictions on how well you can make Prime-like worlds work with a third-person camera (observe how often Other M cheats around this with cross-sections or 2.5D side-scrolling areas). Prime is in third-person anyway when you are in morph ball mode, so this may not be too much of a problem, but then there remains the issue of the aiming system, be it auto-aim or lock-on or something in between.
Bayonetta 2 in the Samus suit is actually the model for how I think a 3D Metroid should play, though the make-or-break factor is in the explorability and interconnected elegance of the map. And we are definitely overdue for a 2D entry. It's almost too bad 2D is now perceived as the domain of the portable line when a side-scrolling, cross-sectional home console Metroid with production values like Tropical Freeze would be a dream scenario.
