I don't know enough about Korean to say if WUNO and SUGO make sense for W and S, but I love the playful idea of 2D. Nice to see three-letter clues be more than mere throwaways.
I'm not sure how separatists is working in 4A (I think of [troubled] as "ate at"), and 1A is busy for a three-letter clue; is [Six-pack Charlie] a thing? Coming up with four initials just so that you can remove another initial feels unnecessary.
"Separatists" is ETA, "troubled" suggests an anagram.
"Six pack" is abs, "Charlie" is "C" which is to be removed from "ABC".
Perhaps clues sometimes seem a little busy because of the (Ximenes) convention that cryptic crosswords clues contain two different hints to the answer?
Thank you so much for your time and for the useful feedback!
Ah, I've never heard of the ETA before—I think that's a super tough reference if you're also going to be indirectly anagramming (and defining a goddess some people may be unfamiliar with). That's what I mean by the clue being "busy" or "hard"—there's just a lot going on, which is fine if that's your intent. (So turning American Broadcast Company into ABC and adding Sun (abbreviated as S) and then also removing Charlie (itself abbreviated in the Nato alphabet)—just makes for a lot; again, totally fine to do! It just made the clues harder than I was expecting.)
It's a learning process... what I can manage, what people want, how to navigate transatlantic differences and so on. Please have a look at today's Teeny Tiny Cryptic (No. 15). I think it's quite a bit easier.