[julio_the_squid]

Are you using a Mac, by chance? The Mac version of Firefox isn't the best.

Linux is not Firefox only by any means - Google Chrome for Linux is very good, and the development tools are identical to the Windows and Mac versions of Chrome (which are the same Safari's tools). Opera for Linux is also top-notch.

Have you tried IE 8's dev tools? Firebug beats the pants off of IE 8's tool in usability and features, for me. Like most of IE, the dev tools are adequate, but lack a decent interface and are not updated or improved often, if ever.

I like Chrome and Safari's tools, but my personal assessment is that Firebug is more comfortable. It has all of the featured you mentioned except possibly the local database inspector.

For the site I work on the most, twice as much of our audience uses Firefox as Safari and Chrome combined, and FF even exceeds IE usage. So not only does it have my preferred dev tools, but is the most important browser for our audience.