The point of the bigger sensor was greater quality, which didn't happen. The quality of the Casio 1000 from 3-1/2 years ago was as good, and it was half the size of the LX3.
You keep comparing your LX3 to this Casio and the TZ5. I've already stated that I feel the TZ5's IQ is inferior and some of the people on LL who replied to your posts seem to share this opinion. The Casio I haven't seen but I don't see you giving any other examples. Perhaps the quality of the Casio you keep referring to is an indication of what can be done rather than and indication of the true capabilities of the digital camera industry. You've said it yourself, Panasonic has chosen not to design to design the best camera they can. Why they choose to this and who they listen to is irrelevant. They've produced a camera and all we have to do is decide if we want to pay for it or not.
So many people have *not* asked for wider lenses, just those forum owners at Dpreview and Cameralabs.
I don't know exactly what the other forums or the unrepresented majority of photographers are saying and I'm not going to try to speak for them. All I'll say is that you're the first person who's disagreed with this whole concept. The TZ5 vs the LX3 isn't exactly a fair comparison, they are aimed at completely different users with different priorities and wants. A comparison between the LX3 and the LX2 it replaces is more appropriate IMO.
You can crop an image taken at a wider focal length but you can't do the reverse to a shot taken zoomed-in. Even more feasible if you don't plan to use the full resolution of the camera.
I doubt you will find what you are looking for in a compact any time soon. The Micro 4/3rds system seems to do what you ask without needing to bother with pixel densities because it is in a completely different league, with a comfortably higher level of noise performance and DR even with +/- 5mp to the current resolution. I am interested to know what you think about those cameras?
Don't forget the micro-lens design! More refined designs can eliminate the side-effects of the wasted space between pixels as Canon and their 5dMkII have shown us.