Thanks for everybody's input. I decided to move the relay keys to the new server but I'm not entirely sure if I start another slow (500KB/s) one or just seed some Linux distros or do something else helpful.
Also I do have a question about IPv6: If I read right I just have to add ORPort [IPv6]:Port DirPort [IPv6]:Port is this correct? Can I specify the same ports I use for IPv4 (443 and 80)?
Also since I have a couple of IPv6 available but a non-exit relay is it still necessary to set OutboundBindAddress?