just back on the grid after 2 days at my mother's house near Gretna...
The state routes that are not included at this time are by the CHM rules: not posted with an actual route shield. This would include regular routes VA 113, VA 192, VA 213, VA 283 and some VA 4xx routes, plus some of the 3xx facility routes. It also leaves out routes that are posted solely with rectangles, but I am inclined to add these at some point.
It in theory could be worthwhile to add the secondary routes that were once primary route corridors (excluding loops of bypassed segments I would be thinking of SR 729 north of Culpeper, SR 711 (old VA 44), the lengthy SR 738 (old VA 51), routes like those that were decommissioned wholesale).
Technically F-series routes are in the primary system but most of these are not worth inclusion as most don't connect to anything else.
There are likely over 100,000 designated and posted secondary routes in Virginia so, yeah, that ain't happening.