I'm just looking for some general examples here of what would be things that would be actual nuisances rather than just symptoms of being a bad roommate, but nothing that would rise to the level of a nuisance?
A roommate situation is not really a "nuisance" issue. A nuisance is when someone is doing something they don't have the legal right to do and it causes you to be deprived of the joy of your living space. Such as someone playing amplified music against local ordinances, drag racing in an area not zoned for the same, smoking when the smoke enters the property of another (when against local ordinances) etc.
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Land Use / Zoning Attorney
As an initial matter, the term nuisance usually isn't applied in roommate situations. However if the roommate's activities are conducted without permission and effectively deny you the use or occupation of the property, then you could have other civil claims. That said, you should probably just sit down with your roommate and work things out. If the roommate is not creating a dangerous situation for you or others it probably isn't worth your time or money to drag things into court.