I managed 15 :) The decision to pick up the last resource at the left or right edge is usually a good one. Also sometimes had better luck waiting out a second of the timer before taking the last resource. A quick restart option would be nice (currently have to f5).
An ability that would make the salesman problem more complex and enable more planning could be teleports. Press space to place a marker, then press space again to teleport to the marker. This could use up N resources, where N starts at 1 and increases by 1 each use.