Venting re" Full Frame

Not really it seems you hadn't adopted a APS-c mind set and are still thinking in FF terms.

The lens you are using leave a big hole in the portrait/studio traditional focal range (50-60 aps-C 75-90 35mm) so it not surprising your frustrated.

As to ring flashes and zoom mounts I'd have thought a studio ringflash like the Elinchrom Ringflash 3000 woudl be self standing like this

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