Swgoh farming flowchart

STOP HERE. From this point forward, characters and ships from fleet nodes aren't required for events or TB. At this stage, you can relax the number of Fleet Hard nodes you're hitting, in favor of more gear. It's also a good time to check on those chapter 5 nodes to see if any you skipped are achievable at this time.

Once ready, Darth Sion is found on 4-D, and is an excellent piece in just about any Sith team.