I've received a few comments about this pergola since posting it, and before I move on to posting some of my most recent projects I wanted to post a few more of the finer details that took a lot of thought and effort.
We created a three way crossover joint on all four corners of the pergola by cutting the corner posts and the beams, so that the beams not only slotted into one another as they crossed over, but also slotted into the top of the posts.
Making clean joints which didn't have to be secured with screws, and were able to structurally hold up the weight of the balau slats covering the pergola.
In order to get the boards to line up on top of the pergola, we had to make miter joints by cutting at three different angles in order to have them sit flush with the end of the connecting board on a diagonal plane.
This also requited cutting the inverse of that same joint on the other end of the board for the same effect all around.