Personally don't mind adamant and rune coming down to be accessable. I think it'd make more sense for adamant to be something that lower nobility had access to in limited quantities and then upper nobility having access to rune in very limited quantities. Dragon would need to go unchanged due to its place in lore. The other three we would need to wait and see the lore associated with it. The t70 seems to have a degree of lore regarding it and it's likely that the t80 and 90 will as well.