Re: New Brass Prep
+ 1 for all of the above.
I don't worry about trimming until I've fired new brass in my rifle at least once, then trim to the shortest if for precision work. If for general shooting, just trim the longest to minimize variables somewhat.
After running thru an expander to round out any dents, you may want to lightly inside chamfer the necks just to make sure bullets get seated cleanly.
Paul