I have found that time and talking about what my goals are helped over the years. Talking about what I have learned about myself and others has helped encourage also. People don't generally like to be told what to do just because I have something exciting going on and think they should be doing the same things, but they do become inspired to do something amazing in their own lives.
Who knows, maybe you will encourage him to take up a hobby he has been putting on hold. He could eventually do that while you pursue new and exciting relationships. For example my husband became a writer in the last five years of our poly lives. All the while I developed new relationships. We are doing what WE want for ourselves. Not what we want each other to do because we are doing it.
He isn't asking to go and find another partner so don't encourage him. Encourage him to do what he wants to do with his life. Things unfold as they will I find and rushing it all seems to create distress and create situations that are not what I wanted. Live and let live I say.
Anyone want to be friends on Facebook?
Send me your name via PM