In the context of

But when this is phrased as "the set of minds included in CEV is totally arbitrary, and hence, so will be the output," an essential truth is lost

I think it's clear that with

valuing others' not having abortions loses to their valuing choice

you have decided to exclude some (potential) minds from CEV. You could just as easily have decided to include them and said "valuing choice loses to others valuing their life".

But, to be clear, I don't think that even if you limit it to "existing, thinking human minds at the time of the calculation", you will get some sort of unambiguous result.