The biggest thing I can say at this point which bothers me is the lack of a Continuous Play Sandbox mode. I do play other games MP so I can appreciate the frustration some feel at it being left out. I'm ambivalent about it since I don't play this particular series in multiplayer.
The lack of multiplayer only affects those who really played a ton of mutliplayer in Anno 2070 and Ubisoft apparently did not think those were significant numbers of players in comparison to the singleplayer population of players. Changing it to a 'mini-game' on a separate map is fine by me, whatever. I don't mind the change to the combat system at all since none of the Anno games were really great at 'RTS' style combat anyways - that's never been the main focus. Well I'm enjoying it so far - but we'll see after I've spent 6-10 hours and am at the lunar phase.