On item 4: I think it would be better to show the highest dir and the filename, instead of just the filename. Most of the time, the directory defines what you're downloading, and the filenames are cryptical.
On item 5: That is already possible, just select the items you wish to change in the queue and click on "edit".
On item 16: I don't see how that would work faster than pressing F8, it would still take one click/keypress to enter the details of a site.
On item 17/18: I just use F4/F8 for this, but if the toolbar would be customizable, I wouldn't mind
For the rest: nice list
