Yes, just mass your starting fleet, maybe build a few quick ships, and start capping the space layers of nearby planets. Then you can have your ground troops swoop in when they are ready and just start taking planets very rapidly. You really only need 2-3 decent regiments and a good strategy to cap almost every planet in the game, at least from minors and the nonaligned faction.

If I remember correctly it only took me a 3-5 weeks to start rapidly taking planets last time I played beginner GC.