If you can help or wish to become one of the maintainers - just start helping.
You can find more RVM related projects at
RVM Github organization.
You can also copy a gemset from one ruby to another.
$ rvm gemset copy 2.1.1@rails4 2.1.2@rails4
This does not require gemsets.
$ rvm gemset copy 2.1.1 2.1.2