Lego Harry Potter Years 1-4 DS

When I read that a release of LEGO Harry Potter: Years 1-4 DS was on the horizon, I pre-ordered a copy. I don't pre-order very often.  I was thrilled.  I loved Lego: Battles DS and Lego Star Wars: The Complete Saga. A Lego Harry Potter is going to ROCK, right?
WRONG!
Since the game represents four of Harry's years at Hogwarts, I'll give you my top four reasons for not liking this game.

1. The controls don't always work.  You think you're aiming at an enemy and you shoot a wall.  I'm pretty proficient in using the stylus on the DS, but it is really difficult to control Harry and the other characters.
2. There's only one character on screen at a time.  When you're controlling Harry, you only see Harry.  I liked the two character set up of Lego Star Wars and LEGO Batman DS
   . If a character is conversing with you, I'd like to see who is speaking.
3. The game difficulty.  The game goes from ridiculously easy to ridiculously hard.  You can be stuck in one spot for what seems like a long time, but the next six puzzles will be a breeze to solve.  There's no consistency. 
4. Finally, did I mention controls?  I did, well, I'm mentioning them again.  Your main control is the stylus.  The other buttons do not do much.  There's a lot those buttons in the DS can do.  They were utilized for the other Lego games, so I'm not sure why they were neglected here.

I've read reviews for the XBoxand PS3 versions of the game, I would recommend buying one of them rather than the DS version.  Total disappointment.