I was wondering if a single-speed ebike would be OK so I did an experiment. I went cycling around the neighbourhood in third gear which is quite a fast cadence when on the flat. I discovered that it's OK for flat and for most hills but is no good for the big, long, 14% hill. Nor was 2nd. Only 1st gear is suitable for that. So a single-speed ebike would possibly work for me if I avoided the steepest hills. That's a pity. I hate derailleurs but I like doing steep hills. There are some ebikes that have hub gears or planetary gears so everything is enclosed and probably lower maintenance.