Whatever bonus it is, it's not only for sect points, but also for avoiding the malus from 10 or less rolls on social, don't forget. I think 1DC bonus for Charms really doesn't compare.I think it really depends on how big the bonus is, and what the techniques look like.
We want Divination's bonus because effectively it's a source of Sect Points from social rolls. But if it's just a +1, that's only ~0.5 of a Sect Point this year. Which I would rate below -1 Charms DC from Runes. Of course, if it's something like +10 then it's amazing and we should probably spend some Sect Points on Divination this year to cap it - as it'll be worth it long term.
And I wouldn't be surprised if another benefit of Divination would be extra actions strictly for social options, either immediately or at some key milestones.