I would say that "Name written on cover" typically doesn't lower a comic's grade. However, if it imprints into the cover it probably will impact in high grade.
I think that Qualified (green) labels for signatures with COA are fine CGC products. I personally have 0 interest in ever owning a PGX case. I don't respect their opinions on comics, and their products are just plain ugly. Voldemort (CBCS, typically not allowed to refer to them here for reasons unknown to me) cases and labels are okay, but, I have OCD and CGC is the gold standard in professional comic grading.