This is a good question. I would say the only differences between HA D3s and flagship publics schools are the size of the school and the type of student you're getting there. A low acceptance rate and a higher price tag does not make it a better school. It just means you are most likely going to find a better, more academically oriented student at the HA school. The top undergrad business rankings are littered with state schools. The state school is actually more likely to have better facilities, more class options, more professors, more money for research, etc just due to the size. Now a HA private is going to get you more handshakes, more family and family friend connections, especially if you are interested in investment banking, accounting, etc. They run in different circles typically and that is not a good thing or a bad thing. If you aren't going to study at a special/renowned program then you might as well save the money and stay in state or at least cheaper.
What does Loyola have that UMD doesn't? What does Franklin and Marshall have that Penn State doesn't? The does Conn College have that UConn doesn't? You're going to have a hard time convincing me to go to Swarthmore for 70k when PSU is only 15 is a good idea. What is Swarthmore better at other than acceptance rate?
You have to know what you want. Business, engineering, comp sci you're probably better off going to a school with a reputation. But science is science everywhere. Chem is the same at HA D3 as it is with the 30k P5 public school. Psych is psych everywhere. English and sociology are the same across the board. Med school they look at GPA and Mcat scores. When you want to get into banking you're going to want some help securing an interview. Maybe a more tight knit community is what a student needs.
Either way it all comes down to what your kid wants and if it can be funded. If he wants a small HA D3 then go for it. If he's so so on where he ends up maybe pass on the 250,000 investment and send him to a state school for 10k a year. If he wants to transfer he can. But if sports were not in the picture I would be sitting them down and saying can you get the same education at a public for half the cost? Unless it's a specialized program I'm taking the cheaper option every time unless it is step down dramatically.