Those looking for each and every episode to focus on Clark may be disappointed with this installment. The majority of the run time is spent on Oliver Queen and his past association with Tess Mercer. This connects directly with his "Smallville"-style origin and intersects nicely with the existing series continuity.
It was already known that Oliver's parents were killed by Lionel Luthor, as revealed during the "Veritas" arc, and I believe it was mentioned that he was presumed dead for a couple of years before his rise back into social prominence. Bringing Tess into that history helps to add some direct conflict to the current season, because it would be far too convenient to have Tess simply assume Lex's role as Clark's nemesis. She needs to exist as a character in her own right, and this episode helps that process along.
I also like the parity between Tess and Oliver. Had Tess been the only one to learn a life-altering lesson on that island, then it might have been a sexist cliche. As it is, Tess all but admits that she has learned to be ruthless from the mistreatment she's received from men. But Oliver is really no different in the end. Oliver considers his ordeal on the island to have been his turning point, the moment he was truly tested and met that challenge.
The difference is how Tess and Oliver chose to react to those trials and tribulations. Tess has taken the darkest path, carving her way through LuthorCorp and setting aside certain ethical considerations along the way. Tess has chosen not to be a victim again, but has no problem making a victim out of anyone else.
On the other hand, while Oliver chose to use his new talents to help those in need and prevent others from being victimized, his methods are sometimes questionable. He does see the big picture relatively well, but he often overlooks the details and the consequences of his actions. In my mind, Oliver exists in the complicated center of the hero/villain dynamic, treading the fine line between humanitarian goals and vigilante justice. As mentioned in reviews for the sixth season, Oliver is very much what Lex might have been.
All of which points to Clark, who has suffered from a self-centered view of the world since the beginning of the series. Oliver has been slowly but surely trying to expand Clark's view, which in the fifth season forced Clark to consider how Jonathan Kent's philosophies might apply to the big picture. That process was derailed by the seventh season, but now it's coming back in full force. Most importantly, Oliver presages the season arc to come by pointing out that Clark hasn't faced his moment of truth yet.
We also have confirmation that ChloeÃ¢â¬â¢s recent mental prowess is the result of Brainiac's intervention. It's coming in very handy now, but the implication of this episode is that the side effects may be a problem in the future. And it's good to see that Lois' issues with having a superhero boyfriend haven't disappeared. It makes up for the ridiculousness of Clark and Chloe arguing about her ability with Lois sitting in the next room.
In the end, while this is an episode that seems to focus on Oliver and Tess to a fault, it's really a means to differentiate Clark and his current lack of experience from those with too much. This illuminates the path that Clark still must take to become the future Superman. In other words, we have another winner for this surprising eighth season.