I beleive that a most usefull feature would be that of BV saving, by default, a new page to (and also open from) the last used folder.
So, if i have organized my BV pages in folders, inside my BV folder, and i try to open a page, BV by default will look in the last used folder. The same for Save.
This is a standard feature of most Windows applications (Notepad, Word, Excel, Photoshop, Autocad, Corel, even Notepad, etc) at least within the same session.
Going further on, a similar feature for publishing the pages would be also very usefull. So, if i have once published a page in "public_html/foldername", it would by default publish in the same folder the next time i edit the page and want to publish it.