I don't get the disjointed part, FO 2 seemed coherent to me (I'm sure many shout New Reno at the monitor now, but that's just one place). Lot's of farms and cowboys(brahmboys?)/ranchers, caravans, people getting by on what they can (gecko trappers, shiny metal miners, mercenaries, farmers again). There was an economy, NCR and Vault City not sharing much made sense, where's the problem?