True. Even though a lot of people expected Tenzin to be the main character for this route, it was kept secret all the way to the release of the first build, if I recall correctly. There was even that funny moment where the Painted Lady tries to put you in Korra's body.
As for who I think we'll play as in the love route... I'm beginning to think an original character might be plausible. Some nobody who became an airbender and moves to the Air Temple in the intro. Who will start to work with Korra during the Earth Kingdom crisis and eventually have a romance with her.
I would prefer an established character, but there's really no one who fits the bill. Aang was close with Katara and Toph, and Zuko was brother to Azula and boyfriend to Mai. There are two obvious candidates who were close to Korra throughout the entire series - Mako and Bolin. Any one of them would be perfect, were it not for the fact that they're already benders of other elements and thus can't learn airbending.
Of the actual airbenders, Kai would be most likely, but he doesn't really have a big connection to Korra from what I remember, only to Jinora. Zaheer would be perfect... for another slave route. Bumi would be hilarious only because we controlled his brother in the other route. The rest are nobodies.
So I'd say it's either:
- Mako/Bolin with some artistic license with how the harmonic convergence worked
- Kai
- or an original character
It's gonna be exciting to find out who the newest meat puppet will be.