Try adding some materials to parts that are smooth plastic/plastic, and maybe try adding more shapes other than ball and block? Other than that, the map looks cool! Reminds me of the Minecraft Console Edition Battle minigame!
Looks really good if i where you i would lower the camera so you cant zoom out to much or make it on a floating island this just gives off a cool terrain floating island vibe instead of parts.
zooming out can affect the lobby though.