In the contemporary practice of participatory neighborhood planning, planners leverage digital support tools with realistic, interactive 3D visualization to support perception processing and to increase engagement among diverse public stakeholders. However, capturing the aspirations of a community lacking design and planning expertise requires a more thorough evaluation and considered design of support tools. We present Land.Info, a proof-of-concept software that allows users to design open spaces with 3D visualization and see the subsequent costs and environmental consequences. To assess how the public engages in design discussion with 3D visualization, we organized three community design workshops for developing a vacant lot. We found that 3D visualization 1) promotes public ideation of user stories around objects, and 2) prohibits ideas beyond spatial design elements. Future research will investigate whether it is possible to aggregate more diverse public aspirations, whether or not visual realism sets expectations for designs, and the potential impacts of expanding the software user base for neighborhood planning cases.