I don't know if I get what you're saying because it's too many words, but essentially I agree.
NIP-29 is different, it's for more closed groups, they deserve a separate client even, very different from the "public square" microblogging use case of Nostr.
Relay feeds and dedicated or niche relays, on the other hand, would fit well in the normal microblogging use case.
The use case i imagine, open to watch but permissioned to write communities. Facilitated by relay feeds.
group A, group B, write to their own set of white listed relays independent of each other. Conversational and communtity "security".
Group C pulls in events from both group A and B, comments on their content and extends the work done, but only on their relays while A and B can do whatever they want without being intruded on or having their signal muddied by thousands of forks, edits and comments they don't care about.