I am planning to replace my current bridge camera with a fixed lens compact. I have decided to give up the longer focal length in return for some improved image quality.

My main interests (photo wise) are landscape, architecture and street scenes.

My only absolute criteria are need for 24-25mm at the wide end of the zoom (even if it means limiting the short-list) and ability to control depth of focus.

In looking at the options, selecting from just the range of Panasonic (purely for exampes; I'm open to other marques):
TZ30 - which goes up to 480mm zoom length
SZ5K - up to 250mm
LX7 - only up to 90mm

Am I going to see any real improvements in image quality between these, at the 25-90mm end of the zoom (which comprises 95% of my photo taking) ?

If I am going to stick with the shorter zoom length options (say 24-25mm up to 90-120mm), what other models should I consider.