Do you guys think it will be a nice addition to be able to label seismic phases on pssac/sac-plotted traces via arguments to the module? This should work for phases already stored in the sac header or specified by the user. Of course, this can be easily achieved using psxy/plot and pstext/text modules.
It sounds a nice and useful feature, but there is no uniform way to label seismic phases in seismology community. Maybe @Bioye97 can open a pull request on GitHub and explain how he wants to label the phases.