I really feel like they had at least another season left in them to dive so much more into Rebecca's life after Jack, reconnecting with Miguel, and their early relationship,. As much as I loved Rebecca and Jack, what Rebecca and Miguel had was beautiful. I think Miguel said it beautifully. Something like "[they] had a void in their hearts that they both filled for each other; Jack for Rebecca and Miguel's kids for Miguel".
I also found teenage/young adult Kate fascinating, tragic, and realistic, so seeing her living at home, working at the diner, while navigating the new Miguel and Rebecca dynamic would've made for an interesting plot. More of Beth and Randall's early relationship and Randall's impact would've been cute.
I know Dan said his vision for the show was to have six seasons, but he really did us dirty by counting the covid season toward that lol
I honestly just miss this show so much and wish we had more episodes!!