My vote is for the Sony H9. I have been very please with mine. You noted that you wanted something that takes good fireworks pictures. Below is my first attempt at fireworks. One thing that the H9 has that the others don't (that I know of) is that it comes standard with a remote control. This is great for fireworks since you don't have to touch (move) the camera to take a picture (its also nice for family pictures). As to the comment about a learning curve, most of the features are pretty standard interface. Some of the fancy stuff is varies some but is explained well in the manual.
Also, the way that the display pivots comes in very handy (moreso than I imagined) for taking pictures of kids (who are short) and reaching above things (crowds, fences, etc.)
Either way, I don't think you can choose a bad camera from that list.