I don't have a PS4 until the 29th, but from watching videos of the OS, I think there are a few immediate improvements they could make to the layout - mainly to move away from that long list
1) have everything in content heading/folders.copy the TV/video layout of a heading icon with a grid underneath so you can easily see content as you browse across.
2) folder for 'recently used' which collects the last games/apps you used, in order of most recent at the top. This would be the folder in focus when you press the PS button. One press down gets you immediately to the last used app.
2a) alternatively keep the flat list for recent items, but limit the number to 4-5 so it doesn't take too much scrolling to get to other stuff
3) have a Games section showing all your currently installed games so you can easily find them. Alternatively, change the library icon so it shows installed games first (not apps) and that could do the same job - needs to be moved forwards in the list
4) have a Favourites section and then let people add games/apps to this, kind of like the Xbox 'pins'
5) put video unlimited in the TV/Video section. I know it's your service Sony, but don't take up a headline icon when many people may not use it.
5a) as soon as there is more than just music unlimited, make a music folder and put it in there
6) let me sort those folders by name, most recently used etc. in the case of TV/Video, give me an option to hide uninstalled apps that I don't want to use or don't have the subscription for, or at least move them to the bottom of the list so my installed channels are first
I'd have the layout something like this
(Playstation services) live from Playstation | recent activity || last used (default focus) || favourites | games | TV&video | music