Let's say that culture ruins speed up your first policy by 5 turns
For tradition, that means those ruins earn 10

and 10

For authority, those ruins earn 5

and maybe 6-12

if you get some kills. You should be smart enough not to clear a camp yet
The numbers are pretty similar for any start/situation. But because progress is all bonus yields, the math isn't easy to do. When something happens is really important. If you grow during those 5 turns, it means that you picked up 30

, which is worth a few points of

as well. But those 5 turns might have no growth or tech discovered, in which case the ruins didn't do much at all. Progress just opens so inconsistently, and there isn't too much you can do to plan around this (because ruins are CS are random).
Sometimes I'll end up playing a game where within the first 50 turns, my opener only gives me 30

, which is pretty pitiful compared to what I'd get from the other two options (which generally provide more culture as well). But sometimes I get like 120

in that time period, which can lead to a really strong start. I think something should be done to mediate how much science you get early on.