This falls under 1) above, and is also covered here below. Was there something new you wanted to convey?
I think 1) should probably be split into two arguments, then. One of them is that Many World is strictly simpler (by any mathematical formalization of Occam's Razor.) The other one is that collapse postulates are problematic (which could itself be split into sub-arguments, but that's probably unnecessary).
Grouping those makes no sense. They can stand (or fall) independently, they aren't really connected to each other, and they look at the problem from different angles.
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