Which is how Red Cow works, which I know CJ has seen the PDF of Red Cow http://iancooper.brinkster.net/glorantha/sartar/redcow/redcow.html
Within the Empire you would want to focus on association rather than a Heortling clan or an ocean-going ship. For my part I think that the association is the operative unit of play in the Empire. You don't have to take on all the burden of creation here. You can ask the players to help the define the association. Aks then players what they would be interested in having their players involved in - what issues would they like to reflect in play and have the association with fingers in appropriate pies. Then create the important npcs in the association. Have them represent a stance within that association or in support of its goals. Perhaps create some important npcs outside the association - its important contacts or enemies. Now your players need to have relationships to one or more of these people (three seems to work well). Make them choose them in during character generation. Of course by adding them to the sheet you are pomising to bring them in to play. Next figure out what crises are afflicting the association, internal and external threats to its existence. An important point here is to make it that at least one crisis should be in your opener, and the npcs the heroes have relationships with should have stakes in it. For heroes to get the chance to emerge, you need conflict. So provide it. Things need to be happening, not about to happen. Then just throw some situations related to that crisis at them to resolve, and use your npcs as the tool to mix it up.
Chris Chinn has a great article on Flag Framing that should help:
http://bankuei.blogspot.com/2006/02/flag-framing_03.html
Out of interest, the HeroQuest session I played with Greg at Continuum was also very much in this mould. The players decided where we wanted to play (Esrolia), who are characters were (farmers, merchants...), what their community was (a family of vintners who possessed the secret of sparkling wine) etc. and then Greg created threats to our community for us to confront.
Ian Cooper
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