On the Wii, the game's controls would be a combination of Sunshine's old setup and Galaxy's new one, adding Wiimote control to the FLUDD and relying on the smaller D-pad to take over the camera. The only real downside to a new control scheme is the loss of the GameCube's unusual triggers, which differentiated between light pressure and a click to control whether or not Mario fired the FLUDD while moving or stood rooted to the spot. I think the problem would be pretty easy to circumvent, though -- perhaps holding both triggers simultaneously while on the ground (which causes the Z button to center the camera behind Mario) could lock in the spray control. Similarly, going into the over-the-shoulder perspective could accomplish the same goal.
So far, it seems as though the New Play Control series is doing more than just adding those new controls, which seems to indicate they're not total rush jobs for piles of cash. Making the FLUDD more fun to use would certainly improve Mario Sunshine, but the tragically small number of FLUDD-free platforming levels is practically begging for some more attention. If Nintendo went back to the game, added in another dozen challenging stages, and spread them throughout the game, everything would be right as rain.
Sunshine is never going to be as incredible a game as Mario Galaxy, but even as a low point for Mario's main forays into 3D, it still stands above other competitors in the genre. With a little care and polish and a new focus on what makes Mario great, Nintendo could easily use Sunshine to fill the depressing gap in our lives formed by the wait for Mario Universe, or whatever they decide to blow our minds with next.
