I'm not sure exactly how to run subsequent round of combat with regard to initiative. It is intended that the players and NPCs can continue to use any slot, or once they choose their slot in the first round, is that the one they use throughout the entire battle? This is important because there are several effects that last "until the start of the player's next turn" (Boost Shields action) or "until the end of the player's next turn" (Evasive Maneuvers action). If initiative remains open, this creates exploitable situations where a character can artificially lengthen or shorten an effect by taking a turn earlier or later in the following round.
For example, if a crew of three players on a YT-1300 are battling two TIE fighters, and the initiative orders is Player Slot, Player Slot, Player Slot, Enemy Slot, Enemy Slot, then the pilot of the YT-1300 could take the third slot and use Evasive Maneuvers, then take the first slot in the next round, causing it to end before his crewmates have suffered any penalty, thus getting all the benefits of Evasive Maneuvers and none of its drawbacks. This is only true is initiative remains fully open throughout the encounter however. If it "locks in", then the exploit cannot occur. However, I read the initiative rules closely and I can't quite figure out how it works in that regard.