It's more difficult to test job-based issues since they involve being at the proper progression in the specific job to establish the exact issue, whereas event content is usually more straightforward and generalized. It should also be noted that the experience provided by BFF event before the fix was at an unbalanced, high rate that pushed players far too quickly through levels. As nice as this sounds, players had an oddly sharp advantage over anyone visiting the game before or after the event period and the effect of higher levels is permanent to the participating character, so solution had to be made.
For the Zero issue, I've forwarded it and will reemphasize the importance with the increasing number of Zeroes stepping forward to speak on it.
The problem with maintaining display is upkeep. You recall the forum was somewhat jury-rigged to function due to being iframed in from a central forum site. You'd usually hear of a user having some issue loading it, being unable to view on phones, etc. I've seen in the past that as browsers change, older pages with odd coding start to break (I've had a lot of trouble with depreciated iframe interaction logic), so to maintain the old forum pages would mean having to keep an eye on it to be sure nothing breaks.
I know you wouldn't like my given excuse, but nevertheless it is a somewhat valid concern. There are more issues I'm sure others could establish better than me.
I don't believe having each other as Potential BFFs is a requirement. When figuring out that NX rings hide the effect, I was able to use it with anyone whom also had the ring. Seems to work similarly to equipment such as the NX couple overalls, Hawaiian overalls, etc. Actually makes me curious about wearing various indirect-couple equipment at the same time...