Attention Grammar Geeks: “Over” and “More Than”

I’ve always been a proud (and yes, like we all are, slightly snobbish) grammar geek. I’m proud to know the difference between a jail and a prison, that to evacuate hundreds of people would be reeeeeally messy, and that they actually feel “nauseated,” not “nauseous” by my grammar snobbish behaviour.
But one definition that has always eluded me is the difference between “more than” and “over.”
My gut feeling tells me that you use “over” when it’s in reference to physical measurement properties (over six storeys high, over eight feet tall, etc.) and use “more than” for non-physical references like (more than 600 people, or more than $400,000, etc.)
Anyone want to weigh in with their understanding of the right way to use these two?



















