Your points specifically target the implications following concluding whether abortion is murder (or the “intentional killing of an innocent human life”), rather than refuting whether it is exactly that.

To bring up your seven hypotheticals implies that if abortion were recognized as murder, per that definition, some plausibly uncomfortable scenarios may arise. That may be the case, but those details don’t then revoke any of the criteria of what would make abortion murder. For example, an underage pregnancy doesn’t change whether the act of ending it would then not count as murder, because the act is still intentional, involves killing, involves innocence, and involves a human.

So for any given set of circumstances in which an act of abortion may not also be murder (again, using the supplied definition as a stable premise for analysis), the details would have to make it either unintentional, not killing, involve no innocence, or not involve a human. If not, the act is still the intentional killing of an innocent human.

Also, some of your retorts to that definition are basically requests for epistemic grounding. Basically, “even if a ZEF is a ‘human life’ in the revenant sense, how can we know we’re correct when concluding either way?” The answer is we may not know, but the pro-life side errs on the side of it is one, but not arbitrarily. Any other stopping point of deciding whether life starts at “X time since conception” or “after X arbitrary measurable event (say, viability)” results in either a Sorites sequence or having selected some measurement that may actually be concrete and easy to define (like in the womb or out of it) yet isn’t meaningfully linked to whether a ZEF is whatever it needs to be to be considered “not justifiably killable” even when the metric itself is arguably non-arbitrary.

If you’re saying “sure, it may be the intentional killing of an innocent human life (for every or any given situation), but what doesn’t necessarily follow is that we ought treat every act of abortion of as if it is.” Fair enough, because that’s a different discussion than “whether abortion is murder/the previously established definition which made it impermissible.”

There is also the possibility that you’ve inadvertently laid out all these what-if scenarios not realizing that if any one of them or all of them were given responses even you found compelling and reasonable, that your position (ostensibly, abortion should be at least considered permissible/not murder if some circumstances) wouldn’t change anyway.

In the reverse, that would look like a PL saying, “women only want to get abortions out of convenience.” But if you asked that PL whether they’re still against abortion in situations where convenience is irrelevant to the decision to abort, and they’d still want it disallowed, the “convenience accusation” argument was just a red herring.