I definitely think a 'Franchise' mode of career could be good, where you just play T20. Would make for a bit more of a bitesize version of career mode. Likewise, having different pathways to the top. Focusing, perhaps more on T20 and then developing in other formats, similar to Warner or Haris Rauf.Its been mentioned:
1) A World view of tournaments, test/odi/t10 world rankings, batter/bowler/allrounder rankings
2) The ability in player setup to pick which formats he plays in so for example he can retire from test cricket - you deselect tests in his setup etc....