Of
course , it depends on what you are going to plant and what your needs are. I would design with liabilities as my main concern. I don't know the grade of you
land. Some of my grade is towards 25 to 30% slope which means no swales for me.
To me, a berm and a swale go hand in hand to create a nice microclimate. The dirt removed to create the swale becomes the berm on the lower side of the swale. You could tweak with that in this situation. You want the swale to be on contour. If the land is flat then a little off contour is not that big a deal. Your berm really doesn't have to be on contour and could vary from from the berm location, but you just have to move that dirt to the place you want it.
A berm does not have to be super tall, but tall might fit your need there. A tall, steep berm might provide a nice boundary around the pergula. You could have an opening for traffic. If the pergula is going to have traffic from all points coming to it and not one "main entrance" then you could do a very low berm with some paths into the pergula.
Again, with liability in mind, I would mulch the swale. No one will be able to recognize it in all probability.
Another factor, you could also
hugel the berm. From my
experience, hugel beds are an investment. I know that hugel beds can work great from the beginning. But my experience is that a long dry time = death to everything on my hugel mound. I don't irrigate.