But, suppose that what you really care about is what you're about to experience next, rather than what the absolute value of the complex number that premultiplies that experience is?

I think this is a more reasonable alternative to "caring about measure" (as opposed to "caring about the number of branches" which is mainly what I was arguing against in my first reply to you in this thread). I'm not sure what I can say about this that might be new to you. I guess I can point out that this is not something that "evolution would do" if mind copying technology were available, but that's another "clue" that I'm not sure what to make of.