Thanks everybody for the very helpful comments. I’ll do what I indicated above (and similar to what @dilumaluthge suggests).
StatisticalRethinking.jl will remain around as an anchoring point and overall README. This will preserve the stars (@cormullion).
As I did with Stan.jl for the StanJulia Github organization, it will have no additional functions (these will all go to StatisticalRethinkingBase.jl), just GitHub organization type docs and StatisticalRethinking.jl will continue to be used for overall testing (e.g. functionality comparisons between Stan and Turing or showing new options such as the recently released ParetoSmooth,jl, AxisKeys.jl and DimensionalData.jl packages).
As @ChrisRackauckas pointed out (and I didn’t know), the size issue is only a problem if the package is dev-ed.
Thanks again all!