Quark is…challenging.
I learned it the “tough love” way. My business won a bid from a client that needed its item base converted to Quark documents for their printer. I had to handle about 3000 items that were done in MS Word. Some of the graphics were done in MS Word. With no training in Quark, I got my ass repeatedly kicked.
Anyway, Quark has some convenient things and some inconvenient things. If you insert a graphic, and later change it, Quark will update it for you. However if you move or rename the graphic, or even move the directory tree that contains everything including the linked graphics, Quark will not find them and you have to manually change their paths. Also, Quark is kind of a pain to export as PDF. It’s got a procedure in its software, but it doesn’t always work. I had to generate all the PDFs using Distiller.
So Quark isn’t something you can pick up quick, but it can work wonders.
Of all the file types you needed to include in your publications, I’m pretty sure just about any graphics software can save/export to EPS & TIFF, which are both for the most part universal. I don’t know about CADs.