Engine mysteriously died in a new car - how can I turn it to my advantage?

Brief version, without any names:
Six weeks ago, I bought a brand new car, with warranty and all that other good stuff. Two days ago, as I was driving on a highway, the coolant light came on, followed by an engine light, followed by my car dying just a minute later.

After it got towed to the dealership, they said the cause was a leaking radiator hose. (Keep in mind, the car is 6 weeks old and has only 850 miles on it!) After they replaced it, it kept acting up, so they decided to hold it a bit longer. (They got me a rental car in the meantime.)

When I called them earlier today to see if they had any updates, I was told this: "Oh, hi there. Uh, we don't really know what's wrong with your car, so we decided to replace the whole engine! We'll get a brand new one tomorrow and it'll be good to go by Thursday! "

When I asked what exactly was wrong, they just kept repeating the same thing. I don't know a whole lot about cars, but a friend told me that getting a replacement engine pretty much destroys the car's resale value because people will wonder what else might be wrong with it. Is that correct? Logically, it would seem that, for example, a 10-year-old car with a 1-year-old engine is better than a 10-year-old car with a 10-year-old engine, but consumer psychology is a strange animal.

Personally, I plan on driving the car for 10 years and 120,000 miles (it's got an extended warranty) before I trade it in, so the resale value isn't a big deal for me. That said, is there any way I can spin this to get some major freebies (e.g., get the car company to shave off a few grand off my loan balance) or something along those lines? Right now, they're just paying for my rental car and nothing else. Given the sheer immensity of this colossal fark-up, though, it seems to me that they owe me a lot more than that.

Got any comments, advice or suggestions?
Thanks!