View should provide Preview Handlers for DWG, RFA, 3DM, DXF, IFC, OBJ, FBX... not just DGN.
A lot of time is wasted if thumbnails are not available. Looking for the relavant files to open takes a lot more time than opening to get a better view, comparing etc.
Having to install other apps or preview applets for all the associated formats is time consuming and bulky.
Unfortunately it utilizes preview handlers from Windows so if no handler is installed then preview is not available.
Also thumbnails are generated by thumbnail providers not preview handler so no universal approach.