Actually in our view these are essentials: Go for a bike all kitted out with a rear pannier rack, mudguards, a strong centre or side stand and ideally with good fitted LED lights powered by the main power battery. If these items are absent on your chosen model, get some fitted at purchase, and get a good quality pannier bag or two to go on the rear rack to make carrying stuff convenient, much safer than in a backpack. (see luggage carrying below)
Lights:
Additional high intensity flashing lights are highly desirable at night and in low sun conditions where drivers vision is compromised.
USB rechargeable lights like the inexpensive cateye.HL-EL042RC/ or a set such as cateye_ampp_200-viz_100_light_set are excellent. We have found Exposure-Lights Exposure lights to be very effective, robust and last for years.
Vehicle Cycle Rack:
You may wish or need to transport your bike to the start of your ride. If so you will need a good quality cycle rack for your vehicle, big and strong enough for e-bikes, such as those available from https://www.roofbox.co.uk/bike-carriers/
Mirror:
I would not be without a rear view mirror – whether mounted on your handlebar, helmet, frame or wrist they allow you to monitor what/who is going on behind you, helping you decide if and when you need to take pre-emptive action like moving in to the primary position or ‘taking the lane’.
NB – I subscribe to the view that using a mirror should not be a replacement for also looking round over your shoulder to check what’s going on behind you – eg when pulling out round parked cars or moving out to take the lane. I think it probably helps for a driver to see the face of the human being on the bike!
I use a mirrycle-mountain-mirror
Tools: Pump wise, I’d go for a Topeak floor pump and their Mini-Morph for on the road, and one of their hexus-x multitools. Chuck in a spare tube to suit your bike, and a couple of good quality (not cheap) plastic tyre-levers and off you go. With that kit someone will be able to sort out an on road issue – even if it’s not you!
Luggage carrying: For carrying luggage safely (ie not in your back) get a sturdy, capacious rear pannier rack, and pair it with a high quality Ortlieb waterproof pannier or two – get a good deal and support the great bike route charity Sustrans here