Yes, sitas, I suppose making holes become easy when you have the good tools ! but I don't imagine making more than 4-5 crossbows, so I do with what I have for the moment... step by step, from small to bigger hole... till it's good even if it demands hours. That's a hobby, we both have time for hobbies!
Gnome, I adjust the angle of the bow for the in direction of the nut, but as the draw length is important, the angle looks bigger when it's not bent.
Yes, Trespa is interesting even if it's very long to sand it. But it can be glued with wood glues and it's resistant. But it's not homogenous, it's made with a lot of paper/wood layers glued together on a hard press, so that's closer to wood fiber than some other industrial materials.
The tiller is made of beech