Idea for the HC3: quiz polls with giveaway subs between sets.
It would work like this: The poll shows the question with 4 multiple choices, chat types 1 2 3 or 4 and you pick x random non subs among those who voted the right answer to gift subs. This shouldn't be too hard to implement on Twitch, I hope.
The questions would be Middle Age quiz questions, I'd be willing to do the research if you agree.
Edit: created an account just to post the suggestion and my username is one letter too long to fit on the left side
As the resident pollster, I can say that we have the technical ability to do this.
My thought is that it's not hard to google the answer while the poll is going on - or once you see what the rest of the chat is voting for, dogpile on it. There is also little streamer interaction, and working out and gifting specific people will take a bit of work (so it's not instantaneous once the poll is over).
I'll raise you with this: Ask T90 the trivia question. We have a means of showing the poll and the options without allowing chat votes to come in. If he gets it wrong, he has to gift subs to the stream. It's more interactive, instant, and you know there will be MANY new subs.