May I suggest another idea?
For some online workshops (panels in Cakespeak), there is an invisible panel (usually 2-3 friends of the workshop leader) who handle the audience participation stuff so the workshop leader can focus on facilitating the online workshop. The invisible panel screens audience questions/comments, and passes along the gist of the ones they think will help round out the public discussion before the workshop winds up.
Expecting the workshop (panel) creator to do the screening while also facilitating the workshop (panel) might be too complicated and discourage some from volunteering. Having the option to invite 2-3 invisible screeners gives the panel creator a sense of support, as well as giving Cake another avenue to help create a sense of community.
I don’t know how difficult this would be to facilitate technically, but it’s a thought...