The extension does come in handy but, you still must navigate through your bookmarks to the position you want to add the site to.
I use the star. That Star it comes in handy also, to temporarily bookmark a site. One click puts it in Unsorted (I put an Unsorted folder in my Bookmarks Toolbar to make it convenient to use.), a second click lets you edit the bookmark. Middle click on it and the Library window opens. Left clicking on it brings up the the Add Bookmark Here ² options window (if you have that extension installed.) That Star also lets me know a site is already bookmarked.
In addition to Add Bookmark Here ², I use Edit Bookmark Plus, Manage Folders, Save-To-Read, Show Parent Folder, and Stay-Open Menu.