Self explanatory; Atleast what was in 6, as those are how you communicate your game not by "victory by napoleon". Civ 4 had a nice blocky graph that visualized better than just linegraphs.
So please, do it better than earlier titles. An updating file per game that tracks everything. This could help a few other things, if this is too heavy (time persistance/opt in so it works for games within 7 days or warn about disk drive use), then only track the necessary variables.
Upgrading earlier ones would be on the wonders constructed, you'd have small icons of the wonders, and on hover it'd give their yields.
On hover, it tells you yields....