So what faction does it seem has to expand the most from it's initial starting place or exert the most effort to meet it's victory conditions?

It seems that Kartdast has the littlest area to expand, the only part that's fairly far from their area of influence is the province in Phonecia.

I think that Romani and Pahlava seem to have to expand the most and wit Pahvala exert the most effort to win.