it lacks sounds more as music: a bit of wind blowing, sounds the man-like figure makes , the legoblock falling and scratching as it moves. maybe seagulls at the very first frames, just before you ralise it is a rather grey plain and not a sea. Music if at all you could go with the iconic "2001 a space odissey" reference (when the man lifts the block) culminating in the block hitting the floor. but that might be a tad clichéed