Weight, hub engagement, and shape all have massive impact on how well a bike performs. With advances in carbon fiber, aluminum, and tire technology, rims are getting lighter, more aerodynamic, and faster. A lighter rim decreases the rotational weight of a wheel, making it easier to accelerate and change direction. Another factor to consider is shape. Deeper, more aerodynamic rims save energy over a long ride, but can be troublesome in crosswinds.
Some wheel systems include tubeless-compatible rims and tires. Tubeless systems use a sealed rim and special tire that locks into place. This allows riders to run lower, more comfortable tire pressures and provides additional protection from flats. This is a special system and can be complex to get set up, but is relatively trouble free once you’re going.