I kind of hated ZZ on my first watch not knowing what I was in for.Had quite a bit of spare time these past few days, so I managed to watch ZZ (by skimming parts of it). I didn't like it nearly as much as the other series, even ignoring the first section. I did like most of the new characters, and there were some great moments (the colony drop on Dublin and the last 3-4 episodes, for example).
I'm excited to move on to some shorter stuff after these three long series.
I appreciated it a bit more on rewatch.
Regarding your future watches, UC OVAs and films are always a visual treat even if the story happens not to click with you.