Comments from @ajrgodfrey that could be incorporated in the summary or possibly introductory sections
Setting good standards for R Journal articles has a positive spillover effects for the R community as authors become aware of good practice and R Journal articles/supplementary material may become package vignettes.
There are various other opportunities for building on this work that should be mentioned
vignettes
legacy educational material
There are plenty of other journals that have a similar backlog of legacy articles. The arXiv accessibility project might be mentioned here. Other journals have converted their back catalogues or are working on it, e.g. journal of statistics education converted their back catalogue from Word to HTML. Particularly smaller journals without paid staff might learn from the R Journal's experience.
Comments from @ajrgodfrey that could be incorporated in the summary or possibly introductory sections