The worst thing to come to Starbound yet ...

Well, I will reserve final judgment until I can personally test out the unshielding mechanics, but, provisionally Im ok with the mine shaft being shielded. As M_Sipher says, its the most likely dungeon to be experienced by starting character, and has low risk, low rewards with quite a few healing spots along the way. Its a great way to slow characters into learning about the generator, and undoing it.