Been wondering this for a bit now. Among my small group we've been doing this "blind" unit selection thing wherein you don't reveal what ships you're flying until the ship placement step. I like it because it injects a bit of drama/immersion into the proceedings. Kind of an in-universe scenario where ships out on patrol don't know what kind of enemy force they will bump into (and it's always satisfying if the person you're playing against has that"Oh good Lord this is what I'm up against?!?" face).
But what about if you're playing someone new at your local comic store/game spot? Do you wait to see what they're fielding and then choose accordingly? Wouldn't they see what you are fielding in response and just change their list, and back and forth?
I have yet to play a stranger, so I'm hoping to see how the community usually operates in situations like that.