The examples you cite are common errors. Organizations that have their feces amalgamated typically have business processes requiring some kind of review, walk-through, or peer inspection of your work. The effectiveness of these systems depends on how rigorously they are enforced and how conscientious the staff is about performing them.
This particular problem continues to afflict me after years of practice. It's been a few years since I actually submitted a board with silk on copper but I have spent hours checking and re-checking Gerbers to make sure none of the silk lands on bare copper.
The KiCAD DRC does not check for silkscreen violations - something I consider a very basic shortcoming. Every time you update a footprint, or re-import a netlist with "Exchange Footprints" in effect, the silk reverts to the size and location specified in the footprint library. Of course (as Edsel Murphy observed decades ago) the locations specified in the library fall squarely on top of adjacent components' pads. That's one reason the silkscreen editing is one of the last tasks I do on a board.
(Some of the board fabs actually check for this fault, and either remove silk from bare copper - perhaps without telling you - or put the job on HOLD and alert you.)
Another common mistake, especially for beginners. In exchange for a serving of my favorite malt beverage, you can be assured that neither your supervisor nor your co-workers will hear of this incident from me. A somewhat related error - pertaining to the board's mechanical layout - is creating an outline that is the mirror image of what you intend.
I think this has been mentioned in another thread in the last few months. My superannuated brain doesn't comprehend the basic problem.
I commonly use 1:1 check prints to test for physical fit. Sometimes it takes some fumbling to make a printer produce a reasonably accurate 1:1 scale. (@Joan_Sparky is going to chime in here and tell me to use 3-D modeling for this. The traditional aphorism warns you about old dogs and new tricks. Besides, I see too many threads on here from people who have difficulty getting the 3-D features to behave properly.)
I also make liberal use of the Gerber viewer. (I like the geda program "gerbv" better than KiCAD's "GerbView"). I make several passes across the board, usually displaying two particular layers at a time. It took some experimentation and practice to develop a set of color assignments, and layer loading order, that makes problems show up in a way that grabs my visual attention.