I just started fooling with bridges and fingers, but I’m willing to toss out my thoughts.
The grinding looks nice and and the diagonal trajectory also. Depending how much room you have between transfer and ring end, I would try to start the tunnel closer to the intake side of the lower and stretch the upper with the top of the bridge. My thinking is that the corner of the lower will feed the bridge better and the whole point is to improve scavenging by increasing flow to the intake side.
I’m finding dual ring pistons to be difficult for bridges. A single ring with the land over the intake gives a lot more room to play with.