Michael Brazier came up with an interesting take on linking Passions with the mechanics of changing history, based on the central insight that Passions aren't just a description of a static character like "good shot 1d6" or "Dextetity 17" -- Passions, by their very nature, have some kind of purpose:

Michael Brazier wrote:
What we've been calling Passions are intentions to achieve a goal. It makes sense, then, that a Passion grows stronger when the goal it points to is achieved, and weaker when the goal is attempted and frustrated. Now if important historical events are points where Passions contend, so that some Passions' goals come about and others' fail; then a motive for Archivists to meddle in events, is to alter the strengths of Passions in more important events (Tobias' "Pillars", for instance.)

To reflect this mechanically, let's say that whenever an Archivist has invoked a Passion and achieved its inherent goal, the players add tokens to the positive side of that Passion, to show that it's grown stronger; and any player can then claim these tokens to lower the difficulty of achieving that Passion's goal in other events. It is not necessary for the events where tokens get added to be direct causes of the events where the tokens get claimed -- it's enough that they're part of the same causal web. (Though it may be wise to let causal distance attenuate strength.)
Symmetrically, when an Archivist has frustrated a Passion (probably by invoking another Passion) the players add tokens on the negative side of that Passion, which any player may then claim to raise the difficulty for achieving its goal in other events (again, within the same causal web.) How many tokens are added, when an Archivist has assisted or frustrated a Passion, depends on how strongly that Passion was invoked during the event -- so tokens go onto a Passion in quantity only when it contends against other Passions.

It seems reasonable, also, to let players assist a Passion within their current event by placing a token on the Passion's negative side, in effect promising to frustrate that Passion somewhen else -- or, symmetrically, to frustrate the Passion now by placing a token on its positive side, which enables an assistance in another event.

The next thought to occur to me was, when an Archivist assists a Passion, that Passion should grow stronger not just in historical time, but also along the Archivist's time -- that is, the Archivist has gained experience, and assisting that Passion becomes slightly easier for him in all events. And of course when an Archivist frustrates a Passion, it becomes easier for him to frustrate it again, as well as for anyone working near the event he influenced. And this can apply not just for Passions, but also for Logoi, which only exist in history when an Archivist uses them ...

So, Logoi also have an inherent goal, which can be assisted or frustrated, and tokens get added to them on positive and negative sides when Archivists invoke, assist, or frustrate them, just as with the Passions. And as a result, when a Logos has been invoked at one event, if its goal was achieved it grows stronger near that event, and weaker if its goal failed ... an effect which the Archivists can exploit. And Archivists gain experience with a Logos by invoking it successfully -- and experience in opposing it by frustrating another Archivist's invocation of it.

A lot of these thoughts came by for me as well - but I couldn't do anything (rules-wise) with them.

If you can, more power to you - I'd be interested!