Riese & Müller have built their bikes to be masters of bike touring. They are some of the only electric bikes that offer a dual battery setup. This means that you are going to be able to go double the distance without recharging. This capability is truly invaluable during a bike tour. On Bosch motors, this takes you from 500 watt hours to 1000 watt hours. There are not any motors offering that type of battery range.
Riding position: You also may wish to check out an e-bike’s riding position before investing in it. For short trips, the riding position might not make much difference, but for long journeys, the upright "Dutch" style with pulled-back handlebars is very comfortable – particularly for tall riders. The same goes for mountain bike styles, though these bikes are not often designed to actually go off-road.
Electric bikes are here in a big way. Liberated from some of the normal constraints of standard bike design like weight and gearing, e-bike design has exploded; if you can imagine it, someone has built it. From cargo bikes to city bikes, messenger bikes to mountain bikes, road bikes, and even beach cruisers, there is something for everyone. The beauty of e-bikes is they make the joy of cycling accessible to so many people in so many ways.