I have been touring on ebikes for some years now, first on a Kalkoff and more recently on a Cube 500 EXC. I don't know if these are available in the USA, but they both make excellent touring bikes. I reckon on doing about 60 miles a day and, providing you manage your battery usage, would expect that to be achievable in most conditions. They are both more than capable on road and will cope with gravel roads. Both came with rear racks, suspension forks, fenders and lights. Specialized have similar bikes in their line up but I haven't ridden one.
A few tips: buy a bike with an easily removable battery, both of mine can be removed with a key and can then be charged away from the bike, in a motel room, for example. Some bikes can only be charged with the battery in place. Buy the largest capacity battery you can, mine are 500 wh and fine but a 625 gives better range.
The latest bikes have low drag motors and are much easier to pedal than earlier models. On flat terrain if well surfaced, I rarely, if ever, find it necessary to use power. My only, small, complaint is that, because of the battery, you may only be able to fit one bottle cage. The suspension forks may make fitting front luggage a bit more difficult.
Prices are UK pounds sterling, Kalkoff (bought in end of season sale) £1500, Cube, £2300 and worth every penny. I shall fear no hill or headwind, for I have an ebike.