Thank you for your comment and attention to detail Colin!
For clarification, the purpose of the base inclination is more to distribute the mass point and not so much to align the top of the drill bits.
Although it does that somewhat as a consequence, in reality the top of the drill bits continues to have an increasing inclination as the drill bit size increases.
To approximate the alignment of the top of the drill bits, I would need an inclination of around 20-25º at least. Which works very well as a display. 
(Let me explain) In the real world, drill bits wear out or break, and especially with larger diameter drill bits, unlike smaller diameter ones, it’s not always worth buying new ones, so people sharpen (at least I do this) the larger diameter drill bits.
This results in a reduction in length and, as a consequence, there are always some drill bits that stand out from the others.
The inclination didn’t involve any mathematical calculation, and I don’t even know what angle I used. I simply tilted it to shift some of the weight downwards and prevent the center of mass from being too high, because when inserting or removing a drill bit, it becomes very easy for the entire support to fall if the center of mass is too high.
In short, it almost took me longer to write this comment than to draw the drill holes. 
EDIT: This is a joke for anyone who followed the project.