Another great point for discussion! First however:
do you agree with Epicurus that some areas of knowledge should be taboo to us as a waste of time and effort, and as harmful to our health and happiness?
I suspect that Epicurus would want to argue that he did not go that far, at least as to the implication of the word "taboo." Here are some of initial thoughts involved in unpacking this:
(1) It's essential in Epicurean philosophy to never let there be any confusion about the ultimate goal of pleasure. Wisdom for the sake of wisdom, knowledge for the sake of knowledge is incorrect analysis. So is analyzing it from the point of view that "wisdom and knowledge are pleasurable in themselves" if we fail to include the rest of the analysis, which is that any activity can generate both pleasure and pain, and so we have to consider all the results of pursuing any particular wisdom or knowledge.
(2) People are different in what they find interesting and pleasurable. I think Susan is talking in part about some recent observations that Frances Wright took a different position on some things than did Epicurus. Frances Wright apparently took the position that she was not interested in, and could come to no conclusions about, life on other worlds or other issues possibly including infinity, eternality, and perhaps even life after death. If that's a correct reading of her, that's very different than Epicurus' conclusion, because he apparently thought that those were vital to address. I am not going to criticize Frances Wright's personal decision on how to spend her time, but I don't think that's a correct analysis for most people, and I think her decision probably limited her impact in the end.
I have a lot more but I will have to come back in an hour or two.