7 or 8, but mostly because of the horde feature and the difficulties of the WRE. After about 20 turns of WRE, I've come to the conclusion that this is how difficult ALL factions, no wait, the easiest ones, should be. It's really great with internal problems stirring up organization and logistics even if the rebels aren't very strong militarily, and they often show up at the most inappropriate of times. I managed to fix loyalty and balance economy before the first hordes arrived, but I've many problems at the Rhine frontline, where I've taken huge losses because I couldn't get my France and Spain area troops there quickly enough to support. After three sweaty battles against the vandals, one of which was a defeat, I've managed to delay them enough to prepare the defenses at the Po river crossing, where I'm in the process of building up my very first army that isn't small or of lousy quality. Hopefully the artillery will turn out effective when the vandals try to cross the river...

Anyway, despite historical inaccuracies the overall gameplay and strategic aspect feels more realistic now, at least if you play any of the more difficult factions, i.e. sarmatians, goths or WRE mostly. But the increased moddability is another positive thing that makes me increase the rating. Overall BI is almost what RTW 1.0 should've been.