So first off, what exactly are our multiplayer options?
Are we stuck with online only? Or can we play hot seat?
Secondly, will there be the option for allied victories? Being able to ally with other players (and AI factions) and win as a team is definitely important. And when playing with another player, it tends to get around that inevitable stalemate that generally happens (once both human players basically divide the galaxy between them). 
Also how exactly are multiplayer tuns being worked out? Normal turn order? Simultaneous turns?
Will there be options for "allied vision" and such, where multiple sides can share vision ranges and spot for each other?
And if there's hot seat, how will visual warnings (like when the camera pans to show enemy moves - if that's a thing) work? Some games end up only showing those from the first player's view. Will each player be given their warnings?