You should add in Calvin Schmid's Handbook of Graphic Presentation into your list Doug -- https://archive.org/details/HandbookOfGraphicPresentation/pa...

Unfortunately I do not see specific discussion of how to make the lines a consistent thickness. It does have notes on how to sharpen your pencil and how to use a carpenters spline to draw smooth curves though.

Technical drawings pens are held upright and have a circular tip that gives a specific line width based on the diameter of the tip.

If you're inking your drawings, you probably don't need to worry all that much about the exact line width and consistency of your pencil work.

N.b. I don't ink my drawings. I've used drafting pens a couple times to experiment, but it's not part of my regular workflow.

https://www.jetpens.com/blog/The-Best-Technical-Drawing-Pens

This will be an excellent addition to the list. Curve lines are a challenge I have yet to tackle in depth.

> lines a consistent thickness

A "ruling pen" would help. It's like a fountain pen where you can adjust the width of the ink.

https://en.wikipedia.org/wiki/Ruling_pen