Delta ending some Florida routes from April

[Tonish]

Any advice on transfer airport for first time indirect flyers with 3 children?
Options are JFK, Atlanta and Detroit

I can't speak for Detroit, but given a JFK/Atlanta option I would go for JFK. Our experience of immigration at Atlanta has never been good and we've missed our connection twice (not that it really mattered, there is usually a flight every hour or so). You also need to change terminals using the internal railway. The outbound leg of the Atlanta journey is quite lengthy and we personally prefer a shorter transatlantic flight.

[Katys Grandad]

Any advice on transfer airport for first time indirect flyers with 3 children?
Options are JFK, Atlanta and Detroit

Not easy to answer but have a look at total journey duration and connection times. It's very hard to predict Immigration lines from 1 day to another but I'd go for JFK because, as Tonish points out, the journey split is more even that way. Whether it makes it worth adding a few hours to the total trip is for you to decide.

Delta are building a new terminal at JFK which will probably be ready by the time you travel so I'd expect the facilities to be impressive there when that happens.

[brizzle]

Thanks for the advice, we were already coming back MCO>JFK>LHR so will look into that option for the outward journey but flying into Tampa.

[Robert5988]

Delta still have four flights a day from Atlanta to Melbourne.

Melbourne is on the east coast and about 1 hour to Orlando(55 miles)