Actually, I quite liked this episode. The case started out interesting, was only sometimes confusing, the ending was a bit flat, but it didn't get lost completely as it happened so often in this season. Brisco wasn't impressive as the bad guy - not a Trent Kort at all but definitely better than that stupid Parsa-stuff.
I disagree that it was weird that McGee asked Tony about his relationship to Delilah. Tony is not that immature or dysfunctional character as some people (still) seem to think he is. He's a multifaceted character, and he had proven quite often in the last seasons that he can be a caring and understanding person. I liked the interactions between these two characters pretty much.
I also disagree that Delilah would have made a better fit than Bishop. I mean, almost everyone would, but I can't see Delilah as a field agent either. (Of course, before that stupid storyline had put her into a wheelchair). But I agree that she is a totally wasted character. If they hadn't made her McGee's girlfriend - with whom she clearly has no chemistry at all, she even has a better relationship with Tony and Abby - she could have been a great analyst working together with McGee in the office while Tony and Gibbs do the field work. THAT would have been a definitely better solution than Bishop. That they had to send her to Dubai to get out of that misfortunate storyline with McGee underlines the weakness of the writing in this season.
Luckily, there wasn't so much Bishop in this episode, but it was laughable when she tried to intimidate Troutman. Writers, people should laugh WITH a character, not AT.