The bike industry is loaded with options to help make your bike more comfortable to ride. We recommend riding your new bike with stock components for a few rides, as they may be just fine for your type of riding. We distinguish between recreational and athletic riders, and the number of hours ridden per week ... the more you ride, the more important comfort becomes.
Here is a non-exclusive list of bike components that directly affect your comfort:
Motor size: Electric bike motors propel your bike forward, and the power level is rated in watts. Common sizes are 250, 350, 500, 750, and then even greater wattages in off-road bikes. Traditional athletic riders forego a motor all together. Recreational and commuter riders have power needs and desires that vary. Steep hills are easily navigated with larger motors, where as a smaller motor will require more “thigh” power.
Seat / Saddle: The number of options here are numerous, and like a horse saddle - there’s a lot of room for personal preference. The size, contouring, and pad thickness all affect the feel. Seats are easily swapped onto the seat post. There are even seat posts with springs, that provide a cushioning effect. Shown below is the popular "Giddy Up" saddle for comfort on recreational rides. With a banana seat style, you are sitting on a large piece of foam rubber, so the comfort is great.
Posture: Handle bars and their risers affect your position, and the angle of your back when riding. Swept handlebars are an example of an option that provides an upright riding position that can be more comfortable versus being hunched over with your neck tipped back. Installing a riser can lift and straighten your back so you are more fully upright.
Tires: Many streets and bike lanes have nemesis cracks and potholes. A bigger tire makes it easier to handle the bumps, while providing greater grip on the surface. Tire air pressure is an important factor in ride safety, and with your riding comfort. Check it frequently.
Tire Liners: In the desert areas, nothing is more uncomfortable than dealing with a flat tire miles from home. Inserts and sealants can help prevent flats from goatheads, so Tannus Armour or another liner is highly recommended.
Lights: Many ebike models have modern LED lights that use very little power, and are wired into the ebike battery, so it becomes possible from a safe riding standpoint to always ride with lights on. Visibility on your night ride is important. Handle bar attached, flashlight types allow you to remove the lights from the handlebar and use them to view around your bike. Many have rechargeable USB batteries.
Fenders: Adding or subtracting fenders can help prevent a skunk stripe on your back, but of course adding bolts and nuts require tightening, and potential rattles. In a desert area with little precipitation, many people avoid riding on the rare wet days, and therefore avoid the need to monitor and tighten fender bolts. Commuters ride every day to work, so fenders can become more important.
Racks, Bags, & Trailers: Safely storing and hauling cargo for daily commuters can be easily accomplished by adding front and rear racks, or a trailer that easily attaches onto a quick release latch. Seat post racks provide a hauling capability for bikes lacking connection points.