I do use the tree view to navigate between playlists/smartlists, but once I pick a one I would like the right hand side of the screen consist of 4 panes (3 along the top: genre, artist, album) and 1 along the bottom (the songs). I can't seem to do this to play/smart lists?
No, you can't. What you can do though is make your Smartlists into View Schemes instead, then you can use the panes or populate the tree. This is simple. In the Edit View Scheme dialog, there's a search bar at the bottom. This works exactly like the search bar in the Smartlists, and saves the search as part of the View Scheme. If you right click on the search bar in your Smartlist and then select Edit (Typing) you can select the entire search and copy/paste it into your new View Scheme.
I like to use the Populate Tree option (and the newer Playlist header annoyed me) so I converted all my smartlists to View Schemes months ago. Playlists aren't quite as easy to convert, but one method is to create a View Scheme that looks for a specific Keyword tag (using that search bar) and then assign that keyword to all of the items in your Playlist. Then, to add new files to the playlist, you actually just assign the keyword and it will show up there. I have a "Totally 80's" View Scheme that was created this way (you can imagine what that contains) and it works splendidly.