First of all, Hangman is not a proven veteran.
Second, if Butler goes back to RG, Wood will no longer need to be "groomed" for the RG position, since we already have a pretty good one, and young one, there. Unless you want to have our 1st roud pick sitting on the bench for the next 5+ years, which makes no sense to me.
If Butler moves to RG, Wood will be moved somewhere else. If Hangartner proves to be good, Wood can take over for Levitre at LG.