Navigation is a little clunky. Provide a few options to suitably navigate, noting the Sychro Pro navigation mode is really good & should be the standard. Revizto is a great example of how to provide options. They provide 4 options - Revit Mode...

No Perspective view – relatively important. Without perspective view there is now way to get inside the building.

Provide users flexibility to adjust 3D View background color. And set default background color to match the current background color for 3D View in Pro.

Consider to introduce global lighting and more render modes in 4D Review.