Yes,
@brinny, I would say there can be the sin of omission.
Anger can take us and our attention away from doing the good which God wants. In such a case, the anger is active sin, including allowing anger to trespass in us. And there would be the omission of all which love would have us doing instead.
So, even if there might be an acceptable reason to get angry, there could be much better to be doing. And we have >
"with all lowliness and gentleness, with longsuffering, bearing with one another in love," (Ephesians 4:2)
Instead of getting sidetracked, even with anger for which there is an acceptable reason, it can be more efficient to proceed forward in "longsuffering" which has us keeping on with someone and maybe trying to help the person do better, Brinny.
For an example, I might have reason why I could get angry that my lady friend is buying low-quality products which then prove themselves to be a waste and which she discards or neglects. But it can be better to be lovingly encouraging with her to get what is worth buying, the first time.
And I think God is in control of if He gets into anger or not. So, I think with God we can decide if we are going to go with anger or with "longsuffering" or simply for our attention to go elsewhere without concerning ourselves with a wrong thing. After all, there always are many wrong things which we could be getting angry about, in this evil world; so it might be good to just invest ourselves and our attention with all the good we can do with God