The UC timeline is my personal preference, and Zeta Gundam is my favorite. As an extension of that, Kamille is my favorite protagonist.
I just really enjoyed watching Kamille grow and mature as a character, he really came into his own.
I didn't expect to love Kamille as much as I did, but I was really touched by how much change he went through and all the strides he took despite the hardships.
I also enjoyed Zeta for the returning characters Char and Amuro. Char as Quattro the mentor figure was really interesting.
I was really drawn in watching Char struggle with this new identity and the expectations of others.
I felt like it was the height of his character development. He was still in a lot of ways that petty jerk from 0079, but it was interesting seeing him try to separate himself from "Char Aznable".
Even though ultimately, he couldn't and even after finally giving in and becoming the leader of the AEUG like everyone wanted... welp, we all know how that turned out.
Amuro's struggle with PTSD and what it means to be a pilot was also heart breaking... I felt so bad watching him try to step up and be that "hero" everyone expects a war vet to be.
His interaction with Kamille and Char was also really great, in meeting his "successor" as well as his "old rival".
I practically fell over backwards when Kamille essentially told Amuro to quit letting Beltorchika give him a** pats and take responsibility for himself. Fantastic.
Char and Amuro's conversation about Lalah was poignant too. You'd think one or the other would be over it but NOPE Lalah's still relevant and still a catalyst for bull s**t to come.
Zeta's side characters and love interests were largely weak and downright irritating, but the strong core cast makes up for it.
The politics were also largely interesting, and the villains were great. I love to hate 'em. Great great villains.
Also, the setting and music is to die for. Especially the sound track, uggghhhhh it's like magic in my ears.
And the fact that Zeta gave me Quattro, the best Char, and the Hyaku Shiki, the best MS, well... that's just wonderful.