It's hard to tell what's the floor, what's decorations, and what's objects in the world, because everything has the same values and shadows are minimal. Stronger directional shadows from objects and characters would help, as would reducing the value range on floor and decorations you can walk over.
The mech's animations look pretty nice to me (though some sway and recoil on the cabin would help with the weight), but the legs slide along the floor as it moves. For straight-line movement, this should just be a matter of making the legs move at the same pace as the movement speed, for the turning animation, if that movement is very controllable rather than fixed, there might be no easy solution (IK on the legs could work, but that's no small task).
Additional "weight" nitpicks: The dust cloud from its landing fades very quickly and thus feels insignificant.
There's no followthrough on the landing, the mech doesn't appear to squish down and then come back up, and this makes it look weightless. This is hard to show from above, but its "arms" would probably splay out a bit, and it would probably pitch forward briefly. Even if you're going for realism, these movements would be there. If you're going for a more Metal Slug-esque feel, then you could exaggerate these movements and give the animation more personality that way.
Honestly though, my biggest problem with the mech is that it blends into the floor. The fact that it's animated while everything else isn't is the main thing that makes it stand out (when it's not shooting, the shooting has nice contrast), and that won't be enough if there are enemies and animated terrain.
