Thanks for the rating. I am sorry about that.
Maybe my tests were good because they were placed on plates that were also 3D printed, so both prints had a margin of error... I don't know.
Maybe print them with a slight scaling.
Capital Letters A-N_0.2mm layer, 2 walls, 15% infill
These were good and the print was fast even with the full alphabet and a few extra letters (and color by height used to make the letters a different color). Just be cautious in removing the brims, if you pull them off too aggressively the bricks won't lock together anymore.