Tahnorra shippers aside, it seems like any time someone even makes an allusion to Tahno joining the Krew people react like this:
“Why should he be part of the Krew? He’s such an asshole, and he hasn’t done one nice thing for Korra or any of the others. He cheated!” And so on and so forth. However, I’m going to show you why I think he should be part of the Krew:
Do you see this guy? Yeah, he was kind of an asshole, too. Now before the fandom goes all Agni Kai on my ass, let me explain. The audience got to see that there was more to Zuko than being another Fire Nation douchebag, we saw that he was troubled and saw that deep down, he was a good guy. (Also, Uncle Iroh was BAMF.)
But think about it, if AtLA didn’t also follow Zuko’s journey, would we have all been so attached to Zuko at the beginning? If the only time we saw Zuko was when he was attacking the Gaang, I don’t think people would have warmed up to him so fast. I mean, the Gaang certainly had their reservations about him. In the same way that Tahno was an asshole to the Krew, so was Zuko to the Gaang; even more so because he was trying to capture/kill Aang. All Tahno did was cheat. (Which was still a dick move.)
The point I’m trying to make is that we don’t see Tahno when he’s not being a giant dick. We actually know very little about his character—aside from the fact that he’s fabulous and obviously spends more time getting ready in the morning than I do when preparing for a date—so who’s to say that beneath all that eyeliner there isn’t a nice guy, as well? In episode 7, we get to see a different side of Tahno, someone who has been humbled. Which is what some us like to call character development. I feel as though episode 7 showed a lot of promise for his character, and I do want to know what’s going to happen to him now that his bending is gone.
I think that he would make a kick-ass addition to the Krew, if for no other reason than to see his interactions with Mako and Bolin.