I have been an avid cyclist since I was a teen and I am now well into my seventh decade. I owned a bicycle shop for two and a half decades starting in 1980. About 2012 I built a mid drive E-bike from one of my favorite bicycles. I rode it a lot for a couple of years. However I have several lightweight mountain bikes I ride most of the time. I have taken several friends riding and they have all loved my E-bike. I bought another E-bike so I could ride mine, and non cyclist friends could ride my other one. This makes it fun to ride with a friend who is not bicycle fit and cannot keep up or enjoy riding with me without the electric boost.
Recently I have started playing with lots of different Electric Bicycles. I used to think the 20" tires on the folding E-bikes were stupid. I have ridden them quite a bit lately and I like them a lot. As you go to wider tires to handle the heavier loads the smaller wheels have the advantage of being stronger and lighter than the 26" to 29" wheels.
Position: My position on the bike, how the bike and frame fit me is important. I want to be able to develop power and be comfortable on the bike. I don't want a little tiny race bike saddle. A great big cushy saddle will interfere with my pedalling.
Battery size : I do not need an oversize battery. I do not use a lot of boost in my city riding unless I am going up a longer hill or have a stiff headwind.
Motor Size: I do not need a large motor. I have ridden a lot with a 300w motor and that has plenty of boost for my city bike. Most nicer bikes have larger motors but I don't have to have a 750 Watt motor for the way I ride a city bike.
Gearing: I need at least seven gears so I will be able to ride the bike without battery power if that becomes necessary. Also this allows me to pedal and keep up with the motor.
Display: No fancy display needed, Many ebikes have a very simple display which tells you how much boost you are using, if the system is on and battery charge remaining. That is all I need. I use my cell phone for navigation. The fancy color or black and white displays showing more information are not important to me.
Wheel Size: Wheel size is not important as large wheels or small wheels work fine for me on a city bike.
Tire Width: Tire Width is quite important. I want wheels that I can mount a 2" or 2.125 wide tire. With my weight and the bike weight I want at least a 2" tire to protect my rims from potholes. I do not want wider tires as they give too much resistance for my use.
Throttle: I don't need a throttle. They are fun when you first get the bike but in cruising and commuting I rarely use mine.
Front Shock: I would rather have a front shock as they increase the comfort level of the ride. However not having a front shock is not a deal breaker for my city bike. I could easily get along without one.
Rear Suspension: I would not want the extra weight and complexity on my city bike of rear suspension.
Overall Weight: I want as light as reasonably possible. I don't need a huge battery and usually the higher quality the bike the lighter weight. I want quality components to be on the bike. Around 50 pounds would be the weight I would be shooting for.
Rear Rack, Basket and Panniers. I would permanently mount a basket to my rear rack and have removable panniers for larger loads.
My Perfect Electric Mountain Bike is just a little bit different than my city bike. My riding position would still be very important as I would expect to be pedalling all the time. I would favor a larger battery. I would favor 26" to 29" tires. It must have a front shock, rear rack with panniers, 3" or 4" wide knobby tires.
Folding, Seven speeds or more, Aluminum frame, as light as possible (under 50 pounds if possible). 20" wheels with 3" or 4 " tires. Otherwise my Ultimate City Bike Requirements would be the same.
I am almost always trying to get the most mileage per charge from my E-bike. I ride a lot on level 1 boost and shut the boost off on slight downhills or tailwinds. I rarely use the throttle unless I am aggressively crossing a busy street or bursting up a steep section of trail. It takes a lot of battery juice to start your bike from a dead stop, in stop and go traffic starting with your throttle all the time can use 40% of your battery. I always start by pedalling.
There are a lot of companies that make Electric Bikes that look like a mini motorcycle. These bikes have wide cushy seats that look like a motorcycle seat. These E-bikes do not work for me. The seat height is not adjustable so I cannot be efficient while pedaling. The seats are usually too wide for me to pedal without chaffing the inside of my thighs. I do not recommend this type of E-bike. .
A lot of people ride their E-bike like a motorcycle. They use the throttle to get started and pedal very little. There is nothing wrong with that in my opinion. I ride my bike for multiple reasons. I love the speed and I like the physical work. Walking is too slow and motorcycles are too fast. 10 to 20 mph cruising is what I love.