>>1682750Curved fascia is easy, just cut 1/8 MDF or equivalent into 12" wide planks, it's pretty flexible so just bend it around the front of the layout.
As for legs,
the risk of the overhang is if someone leans on them (maybe when reaching into the layout to pick up a train, paint or adjust something etc) so it depends on how well attached the cantilevered part is. Assuming the blue rectangles are just for track planning on not separate pieces of wood it's probably OK since your longest span is only about 4 feet. That said, putting a few more legs on is cheap insurance. Maybe a post in the center of the 36x72 rectangle and another towards the south end of the 30x36 on the right hand side
