Longer digital trace further from analog vs shorter digital trace closer to analog
placing the traces further away from the analog seems like it might
  reduce the interference, on the other hand a longer trace is a bigger
  loop area  


You have not shown the power and ground plane. I assume it to be solid underneath the traces as I don't see any other components or via in the region.  


If there are no more traces to be drawn, go for the one with the least trace length. If hte matching is well done, the interference will be really less.  
There will be no big loop area even if you go for lengthier trace. Almost all the high-speed currents will be just below the trace. Only disadvantage is that the signal is close to the edge which might be susceptible to external noise.