Speak on Darood especially Marehan EV32s.
Don't know much as most of y'all are on 23andme. For Qabil lineages, it is best to test on FTDNA. Wouldn't be surprised if many of y'all were closely related to other Daroods, as in sharing an ancestor less than 2k years ago. However, like other Darood clans, MX appears to also contain individuals with haplogroup J. As things stand, I think Darood have the most HG J individuals among the umbrella clans.
Word. That's cool. Rather be Somali bro. Expand on your theory on the preIslamic clans forming. I think Dir was the first to gain Islam along with Darood who they converted. Hence the maternal mother myth. Your mother teaches you the diin. In my opinion I would like to hear more.
We might never know the truth as we descend from, sad to say, an illiterate society. Open a European History Book and with relative ease, one can read about when Visigoths expanded into Spain and when they abandoned Arianism etc. The timelines are not that off either because there are multiple primary written historical sources covering that era.
I think what differentiated Somalis, Afars and Saho from other Cushites such as the more isolated Oromos, Sidamo etc. was exposure to Islam, coastal influences on the Northern Horn and contacts with Ethio-Semitic speaking people (ES). ES does not solely refer to Christian Habashas as the settled centre of the Harar State was Muslim Habasha (Agrobba, Hararis etc).
As for the formation of umbrella Somali clans, they must be a mixture of myth and blood in my opinion. Look at the Somali clan concept of Afarta (Insert Reer) iyo Adeerkod etc. Is it a coincidence that this custom is common place among many subclans. Possibly, with the added glue of Islam, the ancestors of Maxa Tiri speaking Somalis coalesced in a particular area (Northern/Somalia prolly) and began intermarrying among each other leading to the formation of a patrilineal clan based society. The umbrella clans with un-Islamic names might have originally had a confederate clan structure prior to the formation of blood based clans after the adoption of Islam. That is one random theory anyway.
All in all, Allahu aclam!