Very clean, top work. Cut the rabbet is a heartbeat-action. You can kill a lot of hours of work with one little move. I cutted my rabbet with a blade, but this wasn´t the best option. Or maybe i am not the best craftsman for this option. Whatever, the next projct will be milled as well.
Difficult is now the crossing between horizontal and vertical. Difficult because you have to follow with the clean sharp edges. To continue with them on the crossing is the art in my opinion. But with your skill, i have no doubt that it will look great like the rest of your fantastic building.