i'll be trying most of the things on your list i'm sure, it's just taking a while to look and try out all the options that come with each extension.
so far, i can't see myself going back to Maxthon, but i do still miss it. not sure if these are trivial things that i'll soon forget about.
i shall be trying the Downloadstatusbar and update notifier later today - the extended statusbar i'm already familiar with.
i wonder, is there an extension manager extension. something that would allow you to quickly swap between different extensions sets. at the moment, i've set FF up for general everyday browsing use - before, i had extensions simply for web design and testing. it would be nice to keep them separate so the interface doesn't become cluttered up, i.e. you just select a group of extensions for the way you are using the browser.