Great topic! And these are just like you said, "my opinions"
I do think DOMS is a great indication of whether or not you shredded the muscles good in the gym. I'm not sure it's required, but imo, it does let me know I did something. I actually seem to be addicted to the feeling.
One exception is that I rarely get DOMS in my biceps or triceps. I really have to throw something different at my routine to get any soreness there. Despite this, I think my arms are respectable.