I've been taking a look at the map. There are only a limited # of cities that FREE can launch a 2-turn invasion from (either stacks of transports taking 2 turns, or ship chain where they use 2 sets of transports).
These cities are:
Coastal Geek and Lake Port on the south side of FREE homeland
Footloose and Monte Cristo on GONG's former 11 tiler
Freeborn, Sid City and Martin Luther Kind on FREE's 11 tiler
BuyOneGetOneFree on the far west coast of the former GONG land.
There are similar spots for SABER, I am sure.
To me, the most likely jumpoff spot is FREEBORN, with an attack on The Bayou, with bomber support, because they can get as many bombers as they have on the attack.
The Bayou is the ONLY tile we own vulnerable to land-based bomber attack from FREE until stealth bombers. We probably want to add a barracks/civil defense/sam missle battery to it, since they could dump a lot of bombers on it if they attack.
We might want to add a coastal fortress, as well.
The Nursery is similarly vulnerable to an attack from the 11 tiler SABER owns that they took from BABE, if they put an airfield next to Cattauragus.
I am thinking it may make sense to move our EWS out some, to cover where they would have to stage if they were planning a 3 turn invasion, giving us an extra turn, and allowing us to concentrate our defenses around a 2 turn one.
In particular, I might concentrate submarines near the bayou area, to intercept a force at what is probably our most vulnerable spot. It may make sense to move our carrier north, to bomb any carriers they bring. Removing bomber support makes marine attacks much harder.