I agree, the slope is a minor issue.
But I agree that on any slope, you should plant across the slope. In the long run it does cut down on potential run off. And don't get me wrong, where you are in CT, your run off will most likely be from intense thundershowers. Connecticut does not suffer from monsoons!
Those babies can have incredible 'rainfall rates' so planting perpendicular to the slope can help ease that concern.
I think that you can pretty much do what you want.