I think Kawamori did a great job blending stuff from previous Macross Series. I thought we could start a list, if I'm missing any please feel free to add it and mention it too.
-How Michael and the others are imitating the flying of a plane with their hands ( Macross Plus, Isamu)
- The name of the restaurant Ranka works at is the same as Minmei not to mention she wears a chinese dress too (Macross)
Perhaps now is a franchise restaurant, it even has its own comercial, according to Ranka.
-Ranka's brother is the leader of the Skull squad (Macross, Macross Zero, Roy Focker) even the color of the two VF25 resemble of those of Roy an Hikaru (Macross DYRL)
-The entance of the school looks like the main gun of the SDF1 (Macross)
-The part where Alto flies over the city to catch the paper plane resembles of when Isamu was on the desert
(Macross Plus)
-Sheryl says listen to my song (Macross 7, Basara)
-The phone of Ranka, resembles our loved Gubaba , because of the fact that she carries it on her shoulder and under her hair and not because the way it looks (Macross 7)
-I'm not sure About this one, But I'll put it in and wait for someone to corrrect me if I'm wrong, but don't the marks on the red bug thing looked like the ones one the floating stones from Macross Zero?? (Macross Zero)
-At the end when Alto starts shooting like crazy, the frame of the Gervalk looks just like the one of Hikaru when he was with Minmei and he shot at the Zentraedi Pod with the trainning Valkirie in Gervalk Mode (Macross) I loved that frame and right after that the episode ended with yet another great touch like Oboete Imasu Ka (Macross DYRL)
I'm sure I'm missing some, please make you contibution to the list