Having a turn in EB only take a minute is pretty good. The reason why the turns take longer than RTW is because of the extensive script.

It depends on the campaign, however some of the slow expansion is to do with your third question. This isn't a game to blitz on, so we don't want the AI factions to do it either.

Where an independent state is powerful then it is given the military strength to represent this. The Rebel faction is generally non-expansionistic so we stick non-movable generals in their cities, which generally allows the garrisons to build up instead of empty (as the AI is wont to do).

For most factions you must either expand with existing units and go into debt for some time until your economy can catch up, or disband your units and focus on building your economy in your starting town(s).

Foot