Does playing on Proud mode give more rewards?

Does playing on the Proud difficulty (compared to lower ones) give more rewards, like more XP/drops or anything else? I think it did in Re:Coded, what about Dream Drop Distance? Or any benefits at all?

Also, are there any changes to the game aside from health or damage? Any new content?

There are a few things that are different:

There is a secret ending to this game, you don't have to get it in Proud mode, but its much easier in Proud mode as explained here

You also get the "Badge of Pride" for beating it on Proud.

You also unlock the even more challenging Critical Mode when you beat all other difficulties. Beside making the secret ending even easier to unlock that mode is just there to make u hate life, increasing damage of the enemies and actually decreasing yours.

No other changes are listed per difficulty level, not even on the KH wiki article made specifically to list the differences per level by game.