Starting a new city now doesn't dictate the map size or difficulty setting, you can create a new city on any region / map size combination and choose between easy (1 billion cash) medium (100 million cash) or hard (100 million loan).
Each region now plays slightly differently: Alborina has strong sun but little groundwater, Campara has weak sun and plenty of water, and Salina trades power with only one neighbouring city.
Cities that were founded on previous versions keep the original rules.
Improved precision of traffic simulation, and also we do a better job at showing more accurate information in the traffic map.
Fixed charts and drop-down lists that kept redrawing, and laggy mouse movement while the interface was busy.