Heartford could be an interesting one and successful with Europe connections if BOS-DUB-Europe is anything to go by which EI have exploited lack of US based carriers to Europe and even Euro carriers to an extent.
This year will see DUB rise from number 3 to number 2 busiest International route ex BOS over taking CDG.
Just to think 3 years ago (2012) AMS, FRA and CDG were all head and since then, EI have added over 90,000 passengers while CDG has lost over 130,000, AMS lost over 15,000, FRA lost over 250,000.
A question of when additional capacity is added to meet demand by EI.