The end game is a litle dull. Something it is not worth 'working' for it it as we know from a long time we are already winning 


My idea is you should add , as for civilization1, the replay sequance at the end  :


 https://www.youtube.com/watch?v=rmQtEZKcMwg


Of course with a beter graphic. 


For thos who don't know, the replay shows turn by turn what was happening all around the world at the same time. What the other faction  doing and who colonize or took which system ( city) and who build which wonder...


It makes a movie of the game that just happend. It also make us finish the game, just for the knowledge of how the game developed in the other corner of the galaxy


At the end,  it is the story of the game.. 


I think it is a must and not too much trouble to implement I as it was in civilization 1 a long time ago...