This is a feature that is infinitely easier to implement when designing a game than it is once the game is finished. Theoretically, it could be done, at least as far as tracking traits is concerned. I'll sum up what would be required:

- Traits and antitraits for each thing you want to track. That'd be SqualorBonus, LawBonus, TaxBonus, and things of that nature... probably opposed by a -Penalty series of traits. This would be a lot easier if we could actually mess with character attributes and create/display the right ones, but I haven't seen that anywhere and it would make sense if it's in the hardcode.

- New triggers that modify the new traits any time a trait that affects the particular governor stats is modified. This would be done by making at least one new trigger for each old one that could affect governor-type bonuses, and increasing your new trait or decreasing it every time a corresponding trait leveled up or down. The trouble is, I don't think it's possible to do this in the traits file. There's no event I know of that happens when a trait gains or loses points, or hits a new level, so WhenToTest conditions can't be used for this purpose. Furthermore there's no way to tell with mathematical testing (>, <, or =) whether a trait has changed unless you already know what value it was, and no way to store its value in a variable at our disposal... so AFAIK there is no way to construct a trigger that would fire under the conditions we need it to do so.

There are some possible alternatives though. One would be a quick tweak, the other a little more in depth modification that also has side effects.

The easy one would be to give the "hidden" attribute to any traits that you do not really care to see on a character sheet ever. Characters would still get them, but you just wouldn't see the description. If you don't care about anything that doesn't directly relate to governing, you can clean it up to a point where only the governing traits stay shown on your guys' traits screens, which I'm guessing would largely accomplish what you want to. This allows a great deal of customization, and possibly is worth not seeing all the trait details in order to have governor info available at-a-glance. At the least most people don't really need to see piety traits and probably some others I can't think of at the moment, so hiding some for the sake of brevity is quite possibly a good idea.

The harder (and weirder) option would be to convert some of the built-in character attributes to something other than what they are intended to be. You could modify less critical stats like loyalty and piety. Let's suppose we wanted to make those instead show trade bonus and tax bonus now. Attributes are altered by traits via "Effect" lines in the file, like:

Effect Piety 1

These then sum up to determine the total shown for a given attribute. So if we want Piety to show tax bonus instead, we should do the following:

1. Search the whole file, removing any Effect Piety lines from it. This keeps any Piety-related traits from influencing the stat. This may leave levels with no Effect whatsoever, which I'm not sure is legal...
2. Any Level of a trait that gives a bonus/deduction to tax now gets an added Effect Piety in the correct amount. Tax would be in percentages, so we'd have to improvise and say 10% equals 1 point on the Piety scale... meaning a trait Level that gives:

Effect TaxCollection -10

Would have added to it the following on a new line: Effect Piety -1

The upshot is that you can assign any of the already-displayed attributes to your own purpose and remove its old one in order to display exactly what you want. However, there are kinks in this plan. The primary one is that the hardcode of the game will be using Piety and Loyalty as if they are still those things. One potential workaround would be to leave the Piety- and Loyalty- starters' Effects lines intact, and then base your new attribute on that point of the starter being neutral on the scale. IIRC it is 5 for both the attributes in question. Then you'd have 6-10 as positive values, 5 for neutral, and 1-4 for detrimental values. In this particular case the modification has the hilarious side effect of making your bad taxmen more susceptible to being inquidated, while shielding good taxmen a bit. Everyone knows the good tax collectors are always the most pious!

Similar quirkiness would exist for any other situation, depending of course on what the original attribute was used for in-game in the first place. I'd personally find it absolutely hilarious if command skill was entirely based on something like personal security. It's always those paranoid dictator types that make the best commanders...

In the end though, I wouldn't really recommend doing this myself, as it does mess with the game mechanics in a very odd way. I'd probably just hide any traits that I felt were pointlessly cluttering up the character sheet... but since I thought of it, I had to share it in case you're that fanatical about having those governor traits quickly at hand