What are the most critical factors that electric cargo bike owners need to consider when it comes to maintenance and upkeep to prevent costly repairs and extend the lifespan of their vehicle? Are there specific components that are more prone to wear and tear, and if so, what are some strategies for mitigating these issues? Furthermore, how do manufacturers and owners balance the need for increased power and capacity with the potential drawbacks of added weight and complexity? What role do safety considerations play in the design and operation of electric cargo bikes, particularly when it comes to carrying heavy or bulky loads? Finally, what are some common pain points or challenges that owners face when trying to integrate their electric cargo bike into their daily routine, and how can these be addressed through better design, infrastructure, or education?