When working in tangents, once you enter the editing command and pick the first point of the area box, there's an option at F2 "Rotate." This rotates the area box so that it is orthoganal to the cursor. Once selected, it stays turned on. This was a new feature in v11, I think.
As far as I know, you still need to use "Aligned" in the dimension menu. I agree that it would be nice to have the option to make Horizontal and Vertical dimensioning orthoganal to the cursor when working in Tangent.