Oh if only they could have shown Korra and Asami kiss in the final scene.
I think it's to the show runners' immense credit they didn't even *need* to show it. In some ways I think it's even better they they did it this way, even if it was largely out of necessity. It felt a lot more like a real, grown-up relationship where so much usually goes unsaid (a challenge for any writer) because it's unnecessary, than the angsty clichéd teen drama that was the "Mako triangle".
I wish Zuko, Izumi, Desna, and Eska could have appeared at the wedding of Varrick and Zhu Li. Everyone else was in attendance for the heroes of Republic City.
That would be more for the fan's benefit than anything. Logically there's no reason for them to have been there, particularly when they have a nation and a tribe to run, respectively. More than likely they're busy organizing humanitarian aid for the Earth Kingdom/Empire/Republic.....whatever.