A general question...
Despite the generally high quality of Planescape products, not everything can please every DM's campaing needs. So my question is
What changes have you made Planescape from which that you've got the most value?
I'm not interested in minor things like "I changed this person's alignment from CG to CN" (unless that had major ramifications). I'm curious about bigger changes or even ideas that you might not have actually implemented
E.g. Maybe you don't have a Lady of Pain or maybe you have her working on a specific agenda instead of working in mystery
Maybe you have a major war between planes (aside from the Blood War) or a major war between or within pantheons
Maybe you've downplayed or increased the influence of the factions.
But I'd also like to hear what gain you got out of your changes. (E.g. a war between pantheon added adventure hooks for espionage or treaty-making or it alllowed for some sub-plots where agents of the Blood War were covertly backing different facitons)
Alternatively, what changes have you made to official products that you felt improved upon them?
[P.S. largely ignoring "The Faction War" is sort of a given]
It's a pretty minor thing, and isn't restricted to just Planescape, but I cannot envision a half-outsider, hybrid fiend, planetouched, etc. being born to a mother with an opposing alignment component. The embryo/fetus has to be nurtured by spiritual energies as well as nutrients. For full-blooded fiends borne asexually *e.g. from petitioners or spontaneously borne of the plane*, these spiritual energies come from the plane itself, whereas in sexual reproduction, they come primarily from the mother. So the half-baatezu, half-tanar'ri villainess in Bastion of Broken Souls I just don't see as being a possibility outside of a Miracle or Wish, and the suggestion in the BoVD that tieflings and half-fiends are often the result of rape seems unlikely except in the case of not-fully-willing cultists (such as one of the drow NPCs on Wizards website). Attacking a random mortal woman would be a waste of time compared to attacking a cultist or finding an informed, consenting woman *if she's willing to sleep with a fiend, then that's a guarantee that she's fairly evil.*
I also don't ascribe to the idea that Uranus was literally castrated since I view the protogenoi as having been elemental beings rather than beings of flesh.
I know there are other Planescape-specific things that I don't recall.