I agree. No need to reinvent the wheel. I think Salvation was the closest they could get to going on without Arnold and focusing on the original models and timeline and not veering too far away from what made the earlier movies awesome in the first place. Here you don't abandon the original audience while allowing the newer and older audiences further insight to the original stories. I think the last Aliens movie missed that chance when visiting the colony before it got taken over by the Xenomorphs while it was still inhabited by a large amount of people. Same principle.