Install with
remotes::install_github("richardjtelford/ggpalaeo")
This package includes diagnostic plots for squared residual lengths, analogue distances, and transfer function measured/predicted plots.
It also has functions that augment rioja::strat.plot() by adding a second y-axis, radiocarbon dates into the left margin, and a summary diagram.
Make no attempt to make all sensible plots for all objects, just what I need now.