Spoiler
When he say's he planned the whole thing it I got that same giddy joy I get when I read Batman books(not Nolan films). Unfortunately the writers didn't present this plan all too well. I appreciate the effort though.
My fave thing about this ep(apart from willa holland's legs) was the situation he and his mysterious island partner were put in and where it took their relationship. Ollie had no reason to endure that for him and the Arrow dude, desperate, appreciates it.
I also enjoyed Diggle's part in all of this. I also appreciate the moral discussion surrounding detective lance(what makes it really interesting is that he's right).
Ollie vs the polygraph was cool(again more batman(not nolan)), especially that twist and then double twist at the end with Dinah.
The best thing about this was the complexity and consequences. Clark lied on Smallville, Bruce lies in Batman(ino), but here they seem to be really presenting the fallout of such a practice.
What I didn't like was how this ep has been sold for months around Deathstroke.
I'm sure he'll be back, perhaps even the main threat. I do recall how his mask was left on the island in the pilot.