Yes, sorting sounds like a good option. I've just built in some additional scoring that increases points if last visited was recently. This only works for very recent visits (history/lastVisited), within the time frame that history is being fetched, though.

For bookmark/dateAdded, it might help to display the date added and to allow sorting by it as you suggest. I'm thinking about it.

However, the scope of the extension is rather not being a complete bookmark / history manager replacement. Rather a quick search / navigation tool.