i would be research is the key. i have been doing research no these trails, Appalachian trail, CDT, PCT, American discovery trail, and there is another that is being build in the northern east part of America, but this whow i look at it..............
Appalachian trail.............good trail, Michigan to vir. your in the woods, north Carolina to Georgia. you are hiking threw open fields. but with technology on the rise in back[packing people are knocking the trail out in 4 months.
cdt..........another good trail but........there multiple routes to take, and some or most of the trail is done on old seasonal roads, or cattle trails. but you do experice all the 4 seasons in one trail.
pct........goes in and out of towns and cities, so the trail is not fully connected. same with the CDT. plus places will charge a fee for holding drop boxes along the trail.
American discovery trail...........across America, but mostly stays to roads and highways, but does connect, with apple trail, and crosses the CDT, and touches the pct, but does split into 2 trails right before Kansas.
the other trail in northern-east of America.......they having a hard time planning thew cities and stuff, some of it is done, but questionable if it will be completed.