Chris said (again, for what it's worth...) that the timing of the show schedule is a calculated decision. He said the first goal is safety, to avoid having people RUN from Fantasmic! to a prime spot for the fireworks. He said they had faced this problem, of large crowds rushing out of F!, creating a safety issue.
He went on to say that the second goal is to optimize the experience for whichever show each guest chooses to watch on a given night. If a guest finds a good seat at F! or a good spot to watch the Star Wars show, he or she will enjoy that show to the fullest.
Of course he admitted that they hope that guests come to DHS two different nights, once for each show!
I was at DHS just over a week ago, with the "new" schedule. So, take this for what it's worth from our experience.
The Fantasmic theater emptied out very quickly after the show. Fantasmic ended at 9:25, the fireworks started at 9:30. I'd guess that by 9:27, a good quarter of the people were already packing into the exits (we were getting to the exit at about this time - we used the secondary exit that dumps you out closer to Hollywood Blvd.). At this point, we had that "can't move much or look around to see if your family is with you because you have to keep going with the flow of the crowd" feel for the next few minutes. We were probably a third of the way down the walkway (everyone hurrying along) when the fireworks started going off. THAT set everyone moving even faster - fortunately, the walkway opened up a bit or there would've been some serious crowd issues.
We ended up getting to Hollywood Blvd. a couple of minutes into the show. We went to the right, found a spot in the taped off area pretty easily, and were able to watch over half of the fireworks show (admittedly from farther back than ideal, but we were able to see the projections on the Chinese Theater and all the fireworks themselves, plus get a sense of some of the laser effects and such). The DHS employees were waving their traffic control batons to keep much of the flow moving toward the exit, but there were definite issues with people being herded one way and trying to turn around backward to see the fireworks as they were told to keep moving (though it was fine if they just stepped inside the tape lines, etc.
That was the first week with the new schedule, so I imagine they will get the crowd issues handled better soon, but if their goal was to avoid the rush, they failed miserably. If anything, having the fireworks go off right as most everyone is in the exit walkways seems like it makes any rushing/crowd problems worse, not better. Given that everyone sped up once the fireworks started going off, I would think they will have injuries that way as well.
It's hard for me to see how this works out in practice unless they go to a model like MK with MSEP and Wishes (e.g. Fantasmic at 9, Fireworks at 10, maybe second Fantasmic at 11), but that'll be hard to do with the park not staying open as late. Pretty much anything else is going to create a big "crowd rush" problem, unless they run them at the same time, and this would really hurt Fantasmic).
Oh, our take on it was that we were very glad we chose Fantasmic over the Star Wars fireworks, but Fantasmic is by far our favorite show/event/activity/ride at any of the parks. If I had time, though (i.e. if Disney had released the schedule early enough for me to actually plan our trip that way), though, I'd probably try to get to DHS two nights, so that I'd get the full experience of each (I'd certainly choose the Star Wars fireworks over the Jungle Book show).