I've never messed with modding before , but I want to do this:

Removing the Bureau of Labor from the game should be as easy as deleting the entry for it in ImprovementDefs.XML.

As far as changing Coercive to something else goes, I believe that you'll want to find the PatrioticAbility entry in AbilityDefs.XML, and then change the EffectType from PatrioticAbility to something else (an EffectType of Diplomacy will get you a relations bonus of the same kind as the Likable trait, with the Value line being the magnitude of the bonus; DiplomacySharedBordersWeight with a value of -1 will remove the relations penalty for shared borders, though if combined with the trait in the Malevolent tree it might result in a positive relations modifier for shared borders; there may be some other diplomatic modifiers you can find).

Note that the bureau is also directly referenced in global defs. It'LLP need to be replaced in there, or else just rendered unbuildable. 

Give it preclusions for colony and civ capitols. Should be crash-free without letting it clutter the improvements list.

You could just set it to unbuildable for the same effect.