Big Head Zach
Is there anything important in the expansions that wouldnt be in the 2nd edition?
From what I've seen the necessary ports variant is now part of the boardgame art so you don't have to fiddle with the pieces. Also, they've found a way to balance the game for less than 6 players by adding more "neutral army" tokens that go onto the major territories of houses not being played (therefore, if Tyrell isn't being played, there will be neutral armies in Highgarden and surrounding lands that will require a minimum force strength to enter - but like The Eyrie and King's Landing, no battle takes place and no leader cards are used.)
As for the various options for leader decks and Event decks, it remains to be seen whether those options will be retained, or if either a specific selection or blending of those concepts will end up in the "standard" decks.
One thing is for sure - the 4 Player "prequel" variant will likely not be in the new game as it was originally introduced to address the normal map's imbalance when used with 4 players.