My beef with Sunshine has less to do with gameplay (though I noticed a slight deterioration) and more to do with the ending and bonuses.
The ending was terrible to sit through and really quite mind boggling.
However, it was made exponentially worse by only adding a different frame at the end after jumping through some serious hoops for shines and blue coins. I fully completed the game, expecting some neat mini-games, an alternate ending, or some kind of bonus. I was very displeased by my supposed "reward".
Made me hate the game forever, despite it being very fun and entertaining until the treasure hunting portion arrived.
Jam it back in, in the dark.