Libreoffice hacker here. Calc is one of the nicer parts of the codebase. Don’t underestimate the enormous list of features that are required in a modern spreadsheet engine. We’re talking 100s of man-years of coding. Come join us and make it better. Or task one of the available consultancies to implement the features you want.

I know I am underestimating; I have a tendency to do that, so I appreciate the warning. May I ask how many people currently contribute to LibreOffice regularly?

There are about 20 people or so who contribute on a frequent basis i.e. at least weekly.

But we have a very long tail of people who contribute less often.

You can see the commit frequency here: http://cgit.freedesktop.org/libreoffice/core/log/

Come hang out on the libreoffice-dev IRC channel if you have more questions