The line you walk between being patronising and going over peeps heads is a very fine one. I knew one bloke, a Headmaster eventually, but Head of Faculty at the time, who used to ask his audience regularly, "OK?" or "Fine with that?" and their heads would go up and down like nodding donkeys! (Addressing parents).It was a mixture of people. There were few questions as I think I was a bit too technical for the audience. I was hoping to pique interest but I am no public speaker it seems! No, I wouldn't do it again, not my sort of thing
"Are you with me so far?" and "Don't hesitate to stop me if I am going too fast" are things I used to use. Especially when lecturing on Existentialism.
Also peeps in an audience would have their hearts beating fast if they put a hand up to ask a question. So many of them don't dare and then things do go over hteir heads. They get as nervous as you then if not more so, which is why making them laugh and putting them at their ease is so important.
I guess doing it for a living you forget what a challenge it is to others.
Still well done mate. And by the way you ALWAYS think, "Poop, I could have said that differently or explained this better." Or nearly always. Until you have done the same subject a few times.
Maybe you answered most of their questions in your speech!