This is a subject I've done quite a bit of research on, probably more so than most other pre-dents. I'll start by saying I tend to have a more optimistic look on the issue of the high debt as I have two dentists in my family who graduated with around 400k in debt between their undergraduate and dental educations, and each managed to pay it all off within 10 years while still enjoying a pretty solid lifestyle.
In my situation, I will owe about 30k without interest for my undergrad since my parents were nice enough to put money aside on the interest so that it doesn't accumulate. I live in California, and I think I speak for a lot of other pre-dents when I say our system is pretty ****ed. We have two public schools, both of which are considered two of the toughest schools in the country to get into. It doesn't help that they both accept a relatively good amount of out of state students which I'm guessing is done for the extra tuition revenue since our state, particularly our education systems, are broke. Most people don't get into UCLA or UCSF, so we have to look at private schools in our state which are quite expensive. If we don't go to those, we have to go out of state. We don't get into most out of state public schools because they prefer their own students for the most part so most people are left with the expensive private schools in or out of state. Compare that to Texas, where their schools pretty much only take TX residents and the schools are dirt cheap relative to the rest of the country.
Aside from the 7-12 schools that are insanely expensive, I still do believe dental school is a great investment. I plan on pursuing any merit scholarships possible if I get acceptances, as well as HPSP to knock down some of the costs. I've also looked in depth into the various loan repayment programs and I believe that many are very doable if you are smart with your money. That means don't live extravagantly for at least 5 years and becoming your own financial manager. Schools won't teach you how to grow your money and how to plan for loan repayment, so it's really up to you to take charge and learn ahead of time and be exactly prepared for what you're getting into. I could just be optimistically naive, but I've definitely done my homework and still think that for the most part, dental school is a good investment and it's still my plan.