Your interpretations of policy  and that is all they are  are not the consensus here or anywhere else. You don't take into account whether individual blog posts at reputable websites of reputable publications can be reporting rather than opining, and they can. You well know that there is no absolute boundary between the two in magazine articles that have offered some of the best reporting ever done. New Yorker magazine articles are sometimes all reporting, nearly all reporting, partially reporting and no reporting. The policy is left vague in spots for a reason. The line is not drawn at "opinion blogs" but at particular blog posts from reputable publications, and those blog posts will need to be looked at individually  the WP:RS language said "opinion pieces" not "opinion venues". We're going to have to take things on a case-by-case basis, but I think editors have a good understanding now of the principles involved. Your second, third and fourth points are your preferences, not policy at all.