I look at task four of the 2014 Big Spring Nationals. I pull out a
few pilots that started before the last start time so to highlight the value of
leading points (making the competition look like it has a race start, for the
most part).

It's a 178 km task (least distance). You can find the original scoring here:
http://www.soaringspot.com/en_gb/big-spring-nationals-2014/results/open/task-4-on-2014-08-06/daily.

Here are the top fifteen results using the GAP 2014 formulas in FS:

Available Leading points were 78.7. Barker and Bilyk, both of whom
got very close to goal as they raced themselves into the ground, got 75 and 75.1
leading points respectively. Notice that the leading points did not make up for
the speed and arrival position points between first and second. There was only a
less than twenty leading point spread among all those who made it to goal.

GAP 2015:

GAP 2015 actually reduces the available leading points. The
leading points spread among those that made goal is sixteen points. Otherwise
the differences aren't that great between GAP 2015 and GAP 2014.

OzGAP 2005:

OzGAP took the leading points away from those who didn't make
goal. It's up to you to decide if this is right or fair or not. If we are
talking about a race start (which we are - pretty much - in this case), arrival
time points are just a version of speed (time) points.

Just distance and speed/time points:

To me the only real difference between these scoring systems is
whether you want to give the guys that just miss goal their leading points or
not. It can be argued either way.