We have a +n modifier to deal with short vectors and can shrink the head and vector attributes. However, if +n is not used and the (fixed) head size exceeds the vector length, what should happen? Here is an example that compares what happens for geographic and Cartesian vectors (plain and regular):

There is consistency between Cartesian and plain geovector, but the filled-head geovector just vanishes when we hit the critical length = head-length. I think we want consistent behavior, and here are two possibilities:

1. Do exactly as the Cartesian cases do (and then fix the geovector case).
2. Refuse to draw any head if head > length (and fix the 3 other cases).

The second solution would at least draw a short line that

1. Indicates the true vector length (no longer hidden by large head).
2. Indicates the azimuth (which is clearer with the large head).

I suspect there is no obvious answer here so perhaps this warrants a modifier, e.g., +n with no args means stop drawing head if it is longer than the vector length [Default does as in the top 3 plots]. I guess I do not like the current default since the magnitude of the vector is basically lost behind the vector head, but rather than breaking backwards compatibility I would be OK with the argument-less +n solution.

Comments, @GenericMappingTools/core ?