Posting anything by James Bruton here is just cheating. :)
Seriously though, his channel is really interesting, he doesn't go into much about the actual 3d printing aspect of it, in terms of design or printing, but he does a lot of in general discussions about using 3d printing in the wider context of design and engineering.
I think his two biggest takeaways are:
- printing the big bulky parts separately from the smaller, tolerance critical parts, so you can adjust fitment without having to print the big thing again.
- where you can use 3d prints, and where you need to use other material. Like combining extruded aluminum, or wood/plywood to make parts strong, and specific.