Drone-based services in cities will most likely result in high traffic densities (especially during peak hours). Basic unmanned/urban (air) traffic management (UTM) tools and interventions to cope with traffic issues are now well-known (e.g. geofences, layers). There can however be interdependencies between issues and solutions when combined. This paper presents sampled side-effects of using basic unmanned traffic management interventions in an airspace with autonomous point-to-point drone traffic. The samples are based on an interactive simulation and consists of statistics and synthetic images of the simulated situations. We have for instance sampled traffic proximate to a geofenced airport, and traffic from/to proximate logistics hubs. Consequences for UTM development in cities, for the European development of U-space U3 and U4, are discussed.