The effectiveness of 'Often' or 'Very Often' in storyline events (done)

[Kinsman]

My custom campaign has been getting bigger over time, and since I like to use Storylines for slice-of-life or ambient events, my Storyline count is getting bigger as well - it's currently around 140, compared to the default campaign's 90.

I'm beginning to worry about how my important events are getting lost in the shuffle - and even setting them to 'Often' or 'Very Often' doesn't make them rise up as often as I'd like.

I don't really know how effective the frequency settings are, but if they work in some absolute way ("Often is 2x as likely"), what if they worked proportionately to the amount of events total? (I.e. If there are a great many events, the program knows that Often and Very Often have to be stronger.)

I suppose the opposite of those, Rarely and Very Rarely, would need to become less effective as the number of events grew - or else those events would become completely invisible as the database grew.