A. Yes, backend work will be public and APIs made available to use, even if the UI is not.
B. Our internal apps team will be building the UI for condenser.
C. Feedback is appreciated on any blind spots or potential pain points.
D. Yes, actually multi-owner is possible today using on-chain multisig.
E. about limit of 512 is based off reddit model and it's roughly a paragraph.
F. Community standards could fit into description (long field describing what the community is about) or flag_text (describing what will result in posts being muted).
G. Good catch -- URL was left as a note. I'm not sure how granular we need to be. It seems like 639-1 may be a good place to start for simplicity, and expanded to 639-3 if there is a proven need.
H. I agree, though I think that requiring an account creation is enough of a rate limit.

Thanks for the feedback @jarvie!