Desires as a long time user
1. Force developers to have game previews. There are tons of games on the PSN that you cannot see before purchase, in any form. No screens, no vids, just a (very) short bit of text, the Sony licencing blah-blah, and a buy button. Get stuffed.
2. Reduce the size of the half-screen featured game window and increase the size of the search results list. Add some more detail to it.
3. Get rid of the fecking wallet. It is so completely pointless it makes me angry. Sony are nice enough to list their games in actual money, rather than con-artist bullpoints like MS and Nintendo, but then they introduce this bloody thing. Buy anything over £5 and the store lets you add exactly the price of whatever it is you're buying anyway, so what's the point of the chuffing wallet??
4. Make it blindingly obvious which games are full games, which are demos, which are expansions, etc, without having to click in and wait for a separate page to load. In fact, group all the entries for a game or series together. I know you do it for some, so do it for all of them!
5. Make it blindingly obvious which games, expansions and sets I already own.
6. Find out where the latest expansion for Super Stardust HD has disappeared to so I can buy it.