Hello 94501,
First of all, congratulations for being on top of this right now. It's unfortunate that most businesses are just trying to keep their heads above water on the basics. You are a very forward-thinking marketer.
a) Is this a good idea?
Yes, I do think this is a good idea. I've been experimenting with it myself.
b) What might help achieve the intended search result?
1. Domain Authority overall, as well as the Page Authority of these pages.
2. Being on the first page of Google, the higher the better (though they do use content from results lower on the page too)
3. Formatting on the page using easy-to-understand markup like header tags and lists, which it sounds like you're aware of already.
4. Formatting of the question and the answer to make that Q&A relationship obvious.
c) Does it matter that the box answers are summarized from a variety of folks forum posts, so not just one author?
1. I don't think the author, or mixture of authors, matters. However, it may be difficult to format it in such a way as to give multiple answers. Maybe choose the best one, or write your own based on an amalgamation of them all.
d) Might it drive up bounce rate on the actual page?
1. Not if it answers the question.
2. You risk someone not even coming to the page because they have their answer already, but I think this is what Google wants to happen so that wouldn't be a negative ranking signal. And if you're in spot #8 with a #1 Answer Box that's definitely a net gain for traffic.
e) Other considerations?
1. Have you looked into SEMRush yet? They have a feature in Beta right now that lets you see all of the enhanced search results (including Answer Box, Knowledge Graph and others) for which a site ranks.