When leaving a comment, feedback, or suggestion, please wait at least 24 hours to get replies before you decide a suggestion or piece of feedback is without merit. We're not here 24/7, and can't answer things as immediately as perhaps a person might like.
Having said that, we're a community about coming together and sharing our different experiences with a disorder. "Mild" dissociative disorder is still the same real disorder as "serious" dissociative disorder, as are all the depersonalization disorders you listed. I wouldn't want to break them apart.
If a forum doesn't have a lot of the topic you're interested in, that's usually a sign there's not as many people interested in posting on that topic. (We're just moving electronic bytes here, so there's no "hogging" of anything.

) So unfortunately, I don't think it merits its own sub-forum at this time.
If you're interested in the topic and want your own space for it, however, I'd encourage you to start a social group and let people know it exists so if they want to join it, they can.
Thank you for your thoughtful and kind suggestion.
Best,
DocJohn