Improvement of Portal:British Museum both for content and for looks and presentation: for example w:Poets' Corner#Burials shows a neat way of using images in a table such as already exists for author pages.
Work on any of the author pages linked from the portal (biographies, addition of works).
Creation of any of the works from those author pages; EB1911 and DNB projects both should be interested in this specific task.
Adding any further author pages to the portal that should be there because of association of the author.