The game had a few difficult spots for me, but I have it fully completed. Every high score on the challenges is beaten, every mission is completed, I got the Manaphy Egg, I even finished the Scouter, or whatever a Pokémon Ranger's version of the Pokédex is.
Now it just sits in my DS case, sad and alone... Maybe I'll sell it on eBay, so another person can enjoy it. Well, except for Manaphy.
I'm not keeping tabs on this thread, so if you want my Pokémon Ranger game, or have a suggestion as to what to do with it, you'll have to PM me. It's great if you love drawing circles at high speed. :P