No Zeus, War in the Pocket would not make the sense it should stand-alone.
It kinda emphasizes the main weakness of UC Gundam, it only really has one entry point, the original show or the compilation movies, but those are old and not as easy to come across. Unicorn, kinda works as an entry, as it brings a lot of the history as lore and not as back-story.
In a sense, what I would suggest is to watch either form of the original and then it opens up, as long as Double Zeta is watched after Zeta and CCA is watched after Zeta or both. 0083 is funny that watching it in chronological or release order would quite change the ending. (And Narrative after Unicorn, but even that is quite a bit after what most people consider the main part of the UC)
Also, both F91 and Victory are part of the UC, but take place so much later that they are mostly stand-alone.
With the sequel to CCA on the horizon, now would actually be a great time to get into the UC.
Are you arguing that 0080 doesn't work as a standalone? Because it absolutely does.
---
(\/)(\/)|-| There are precious few at ease / With moral ambiguities / So we act as though they don't exist.