I converted mine to differential axle and have lots of rear sprocket options for the Peerless model 100 differential. My drive train is the least home made looking part on the trike.
It's a heavy tri-ped so I'll need a somewhat taller gearing ratio than the "ideal" one in the gearing chart (3.4 gearing ratio wouldn't be applicable) to get up and going quicker. With existing 10:60 setup it's crazy quick off the line but stalls at 20mph and starts overheating.
So you say go ahead and order up a few rear sprockets in the 40-45 tooth range and experiment?
I'm going to start a separate thread on timing. Putting the Ducati CDI in there. You can see from the photo my 6v existing wiring is held together with alligator clips for testing.