Global Triumph

I second that!

That would get tricky since your alliance members would still be able to attack you and visa versa.  All no air support over your allies country you'll get shot down.

you can have an alliance without having treaties now. 

think of the trust/distrust issues that could be started between rival alliance member if you know your ally could turn on you in a moments notice.  more real world then "in seven days i'm going to attack you"

if you want allies providing air support over you, they need corridors to do so, or you need allies that are not behind you.

the 7 day treaty is too long of a time in this game.

i think 7 days is very small, considering how a single game take at least 3 months.