Renders in 0,3 seconds per frame, with motion blur and nodes 4 seconds at 720p resolution. 
Looks good, you are getting some jitters in the volumetric light, however.
Is that halo or true volumetric?
Just a halo (Samples: 7, Halo Step: 11, Soft: 6.7). I wonder how I could get rid of the flickering… Maybe just more samples and steps?
More samples and more steps, your single frames times are so low, you can definitely get more quality out of it.