I noticed the bottom of my bucket was rusty the other day, so your post caught my eye. I remember Dad dosing the moldboards on the old plow with used motor oil so they were easier to roll sod the next year. But I've decided that I've been neglecting to use my bucket enough this year so I'll try to do better, haha.
As far as back dragging, I have been pleased and rely for the most part on reversing the back blade at the 45 degrees mentioned, and using the front loader bucket with "Edge tamer" runners to stabilize the tendency to rock on the short wheel base CUT (L2501). Worked well smoothing the 150 tons of 3/4 and less road base that comprised the walking path at our church.