UniChris

Honestly there's not much need of a map for the NCT/SCT. The new Elmsford connector means there's only a half block discontinuity at the street crossing, which should be quickly figured out, and the section on the road shoulder between Briarcliff Manor and Millwood is logical northbound and no big deal southbound if stay on the shoulder the whole way and you miss crossing back over for the brief stretch that momentarily goes back into the woods on the east of the highway. Apart from that, knowing where you can get food/water - eg, Elmsford, Millwood, Yorktown Heights, just west of Baldwin Place, etc. It shows up on google maps cycling routes and directions, too.

The MA/CT part sounds interesting. The Farmington Canal Trail is quite nice between New Haven and Westfield (just southwest of Springfield), but there's still a 10-mile road gap in the middle (which I got teleported across by family). Those trails do have a printed map available at many of their information signs, though again apart from the road gap in the middle you hardly need it - the water stop information didn't seem particular reliable (though the new Cheshire facility is great!) and for other services google or whatever maps are probably better. Rail routes have a real habit of avoiding the consumer-ish parts of towns and this is no exception - for example most services in Avon and Simsbury are missed with the exception of the turn at the edge of the parking lot of the Drake Hill shopping center, and you pass a large shopping plaza in Hamden but that's too close to New Haven to typically need to be a stop. (There are some trailside breweries however)

Did centuries on both of those this past summer, but probably won't personally be trying to connect them - you'd still have to get between the former Put route a minimum of six miles into NY, and what is essentially the middle of CT, so I did them on separate trips via Metro North and the new cycle-friendly Hartford Line.