Catrike introduced some tempting views of the Eola, a new recumbent trike model that will hit the streets sometime in 2019.
The Patterson Metropolis is an economical way to extend the gear range of an 8-speed Terratrike.
Using the Shimano Nexus internally-geared 8-speed hub on any trike gives you the enclosed reliability of planetary-geared hubs, but it's a bit slim on gear range -- particularly with a small 20" wheel on