So far not possible but as BA has been saying this is just the start, they will be adding more resources till the final version comes out. So far you can create three types of stadiums Oval,Circle & Square. Ropes type can be Short,Long,Wide each has two options if I remember correctly. There is one concrete that can be used, three stands type long medium and short, each can be highly configured. There are lot of hill types that can be added, roads, cars, furnitures like chairs tables, three food joints (burrito,chicken & coffee/donut). You can add cars buses, dustbins, toilets.