Just to speculate a bit further. Having worked in the rooms at Kingsway I would be that a bunch of the textures you hear on the early records were from they used the sound of those rooms to augment the performance. If I read correctly Globe was sort of the same way. Big open unique space with great tone.
I still to this day try and emulate the sounds I got at Kingsway. I NEVER am able to. And Trina certainly knew those rooms better than almost anyone.
Michael Greene