Since the DS on the PS1 I have felt "this is the perfect controller" in terms of basic lay out and feel. The nuance touches and improvements have been nice, so I have no real complaints if they barely upgrade it for the PS4. Maybe increase battery life and improve rumble feature a bit as others have mentioned and I am fine with just that.

Fix the trigger buttons as others have said L2/R2.

Don't change location of any of the buttons and symbols on them. If someone can't learn 4 character symbols than they should move on to new hobby.

Keep the controller the same size. No need to make it bigger just to fit the hands of Kratos.

I honestly don't mind if the playstation controller stays the same forever, i love it as it is. I don't even see what the problem with the triggers (L2, R2) is, i like it, but i do admit xbox triggers (LB, RB) buttons are superior. The playstation controller just seems fine as it is, why fix something if it's not broken?

I think the controller should have an improved look that goes with the design of the next console. A more modern designs, but maintaining most of the same form factor, and maintaining the button layout as it is already. Also the triggers need to change shape because your fingers can slip (make them concave), and it would be cool if in the parts where you grab the controller they could add some textures to enhance the grapple. They should add LED-lights below the buttons so that depending on the hour the square, triangle, circle, and square buttons, can glow in the dark :)

Maybe they can add more shoulder buttons? How? I dunno, but it is better to have more buttons when developers are porting PC games to consoles. XD

the D-pad and action buttons are preassure sensitive, so no clicky for you XD

Bigger. Analog sticks moved up slightly. Concave tops. Vita's D-pad. Break-apart idea implemented.

a tad bit larger, better triggers, better analog sticks..as in maybe use concave this time and try something new

I'm thinking a biometric controller might be interesting

.... Get out.

tbh i totally forgot about that

I use trigger extenders, which are awesome. Really, if you don't like the DS triggers then get the extenders. I don't remember the brand I use, but they're like this: http://www.amazon.com/Pelican-Triggers-Controller-Attachments-Playstation-3/dp/B001AW156U/ref=sr_1_7?ie=UTF8&qid=1351987694&sr=8-7&keywords=dual+shock+triggers

I also use analog stick extenders, but they're not as big a deal. Still, I like them. I wouldn't mind if the DS grips were flared out a bit more in order to lessen wrist bend, but then I have some wrist problems.

I absolutely do not want a tablet controller. No offense to the people excited for the Wii U, but I hate looking away from the television while while I'm playing, especially if developers throw in gimmicky stuff (and you know some of it will be gimmicky). Anything relevant can be displayed on a mini-map, a separate screen that pauses the game, or best of all, a HUD. More importantly, a touch screen would be costly, which would result in a lower budget for the internal components. If the price is going to be the same, I'd rather have the extra horsepower.

Now, all that being said, there is one thing holding back standard controllers, where I do like the Wii U's potential, which is that there aren't enough buttons. Buttons are part of the reason why I like some games much, much better on PC. To help deal with that, I wouldn't mind seeing a couple of extra buttons appear on the DS, perhaps on a little extension below the sticks.