I noticed that in beta as well, So it looks like Underworld Trading then if I want heavy armor materials to make tanking gear for synthweaving?

I know I'm taking Archaeology as my gathering skill. I'm torn between Artifice and Synthweaving as a crafting skill. I would like to take Diplomacy to assist in grinding light/dark side points. But does Diplomacy give me anything as a Tank with either Artifice or Synthweaving? Would rather not take Underworld Trading if I don't need to. Any thoughts or suggestions?