Here are some suggestions for custom assets:

1.Scattering of custom assets
2. Provide a builder to create natural assets such as trees and share them online (wind characteristics)
EX: SketchUp Warehouse
3. Custom decal + pattern repetition, spacing, linear options
4. Lack of assets and reflection values for underwater expression (available as an option in Lumion)
5. Display and place proxy files for D5 assets when SketchUp sync is supported
6. Sea and waves option

Even if you just upgrade the above, D5 is the best in this field.

Thank you so much for your suggestions. We are looking into them.