check to see if love is reciprocable before allowing process to proceed".

Does this mean extrapolating how person 2 will feel after they spend more time with person 1? Would you take into account the presence of a third person who might steal the affections of person 2? I guess we could solve love triangles by duplicating people.

Love also doesn't seem to me like a binary event, we'd want to allow relationships that would progress to any level on a mutual love spectrum and then stop people from falling deeper in love when their partner would not follow.

Here and elsewhere, I don't really see the "don't let things get too bad" solution as categorically separable from just bloody optimizing the process already.

E.g., sure, a generate-and-test mechanism like you propose for relationships is an improvement over the existing no-test version; agreed. But I see it as a step along the way to a more fully optimized system... for example, one where the people most likely to construct mutually satisfying relationships (which include reciprocal-love arrangements, if that's what you're into) are proactively introduced to one another.