R is king for analysis of tabular data e.g. data exploration, model fitting, and visualizations where all the code can be contained in one .R file.

R not as good as other languages for production-level work though or for analyzing non-tabular data (e.g. streaming data, or data in unstructured formats).

I also find R packages (writing, installing, documenting) to be a better experience than the python packaging system. i.e., very little rewrite necessary to convert a bunch of R code into an R package.