For comparison, Australia Post went with mostly 3-wheel electric bikes for local deliveries (3100 out of 4100 EVs in the fleet mid 2022). https://auspost.com.au/our-stories/inspiring-stories/sustain... there's a photo in the link. The low noise compared to the previous powered bikes is really nice.
Compared to the old step through moped they had this new trike is a big improvement. It has shade and it carries far more mail. But it is bigger and I can see it may sometimes be less "agile" on badly maintained pavement and grass. The mopeds used to scoot around like zippy little dogs