... What I imagine is something like FRR + x...
Is the team ready to implement this? If so, just do it then, because this is pretty much exactly what people have been asking for.
It just that Phil earlier made a point that creating any kind of algorithms is not desirable.
BTW, this could also be made as an "activatable" module.
I believe, if I remember his post correctly, that Phil said an algorithm should not increase difficulty or complexity of the UI for users. Our system is pretty advanced as it is, and any new feature has to be weighed against the increase in complexity. I think that a very simple algorithm (if it even deserves that name) of a delta applied to a known variable would be somewhat simple, and I think that as long as you maintain a default value of 0, users who want the additional functionality could use it, while those who are content with the current system should not have to do anything additional.
As I said, this is just one suggestion, but I think it addresses the issue in the most straightforward way. And I agree, that if you further have this as a feature that a user can "enable" for their account, they will have even less of a learning curve.