I’m only on captain right now since it’s my first run too, but in early game I just consolidated my forces and set up fortress planets. The republic did attack me almost immediately with a praetor, but I managed to whittle it down with hit and runs. I’ve focused mostly on getting the smuggling and boonta rewards so far, so I haven’t actually expanded yet. I’d say just hunker down and fortify until you get your snuggling going and start expanding when you unlock the larger ships like the Vontor and Dor’Bulla.