Are there any tools to convert R to JS or Python, or... any other common language that doesn't require a 60mb runtime distribution?
If you don't want to use R, Pandas in Python provides very powerful data frames (which are likely faster for many cases). However, it depends on NumPy, matplotlib, and a few other libraries, which probably total more than 60 MB.
See http://r.789695.n4.nabble.com/R-in-the-browser-td4667985.htm...
But the JS blob ends up being like ~15mb!