This is my approach: address-bar autocomplete only uses bookmarks as suggestions (well, and open tabs). I almost never open my bookmarks, nor feel the need to organize them. I'm really pleased with the way Firefox has implemented that autocomplete: by default, Firefox autocompletes the domain names (with typeahead) while you're typing, while full bookmarked url's are just a down-arrow away, sorted by most recently used. It means I never have to bookmark bare domain names: as soon as I have a page bookmarked on a domain, Firefox will also allow me to quickly navigate to the bare domain site. And for individual pages, I can just type two or three letters (not necessarily the first few) to directly identify the page that I want to go to.

Obviously that means I'm using split url/search fields in the address bar, or that wouldn't work as easily. I also heavily use Firefox' keyword search to avoid doing a round-trip through a search engine if I already know which site I want to search; mostly using the same prefixes that DDG uses, so I don't need to adjust too much if I find myself using a different computer.