The navigation of Elisa is somehow inconsistent because it mixes tags (artists, genres), formats (album, tracks), and history/context (recent/frequently played, now playing) in the sidebar of the collection. 

IMO this is problematic in several ways:
* It make the navigation ambiguous. Should I look in Artists or in Albums for an Album of Artist XYZ? 
* Each sidebar entry is fixed to certain display format (album, track), which makes sense for the format entries, but not for the tag and history/context entries. 
  * Example 1: I might be interested in displaying tracks of an Artist or Albums which contain tracks of an Artist. 
  * Example 2: I might want to see frequently played albums.
* It narrows navigation down to a fixed set of navigation tags and makes it quite hard to extend to further possible tags (e.g. year, publisher/organisation, Album Artist, ..), since this would blow up the sidebar and make it hard to catch. 
* Tag navigation is not supported in combinatorial ways. 
  * Example: I would like to find all tracks of some genre in some year ... 


Suggestion:
I would suggest to implement tag filtering in a unified/combined album/tracks view: 
* It should be always possible to switch between the album and track view mode. The relation between tracks and albums should be, that an album is displayed whenever at least one track of the album surpasses the filter (This is the current behaviour, e.g., in artists view). One may highlight these tracks in the album view mode. Filters are preserved when switching the view modes.
* Support multiple filters with AND (e.g. genre chillout, year 2000)
* Support grouping by tags. E.g. Group album by artists. 


Quick navigation thoughts: 
The above idea just describes the most general navigation, but of course the current tag entries might still be desired for quick navigation without the need to type something. Thus I would suggest to keep them as a shortcut to a the proposed view, which is preconfigured. E.g., the Artists view would simply shortcut to the proposed view without filters, artist grouping and album view mode.