I have a similar answer - I'm a data analyst at a company full of rubyists. I can (and do) use R for most of my analyses, but there's a cost in transparency -- I can't realistically ask someone to review my R code when they don't know the language, and the bus factor is high if anything I write in R is at all important.

That's why I'm trying to use Ruby where possible, even at the cost of a small productivity hit. The benefits of others being able to read my code far outweigh the few extra minutes it takes for me to do something (and in many cases, the sheer brevity of Ruby as a language means it's faster, simply because it's less typing).

I'd love to see SciRuby become a more useful project, and I'd love to contribute. Unfortunately, they don't make it especially easy to get involved -- the mailing list points people to the roadmap, but it's not at the level of detail where someone could jump in (and the component gems don't seem much better), so it's a bit hard to know where help would actually be useful.