Age and stage can mean a lot to some people, but in poly it doesn't seem to be as much of a potential issue due to the nature of some poly dynamics. It depends on the dynamic you want. If you want a primary and several secondaries then maybe it would factor in in terms of the stage of life differences, but not necessarily. The rest is totally up in the air really and dependent on a good many factors including interests, amount of involvement, what one does in everyday life etc.
Anyone want to be friends on Facebook?
Send me your name via PM