Your plan looks good. I have the sunset valley rail bender and it works really well. Its a timesaver over making your own. it will bend rail as tight as you want . I bent rail in a 21" circle for may turntable.
Also I run locomotive along the edge of my modular layout for about 4 yeas now and have not had an accident. I always follow each engine on its first run to make sure there are no problems. But at the speeds we are going its not much of a problem. I have a curved trestle on my indoor as you have seen and have had no problems…