I have been looking into Agenda as a possible Evernote replacement, and in many ways the feature set is substantially more impressive. However, there is one aspect of Evernote that I particularly miss: the easy-to-scroll note list in the sidebar.
Agenda has a sidebar with categories and projects, but as far as I have been able to discover, there is no option to display a list of all of your notes (perhaps with short previews of the text contents) and easily move between them. This navigation feature (also present in OneNote, Ulysses, and Scrivener) is extremely useful when working with large volumes of notes, and in order to make the switch to Agenda I would need something of that description.
The current workaround is to use the table of contents feature (clicking on the project title at the top of the page creates a popup listing all of the notes), but what is missing is the ability to easily flick back and forth between notes while keeping the list visible at all times.
Please let me know if you would also like to see something like this — or if you have any feedback or further suggestions.