I finally set this aside about a week ago. My nephew loves the game (well, he has Diamond), but his inability to read has hindered him greatly the whole time. Being 6, he also gets lazy and selfish about the game.
So I got sick of him demanding unfair trades, and for me to give him everything I got. Plus, I decided the Battle Tower was a luckfest, and while I was very close to having in my boxes the entire Sinnoh Pokedex, I just didn’t feel like finishing. So, I got Action Replay DS and have been giving Daniel Level 100 Shinies of any type he wants, 5-10 a day when I see him.
I enjoyed the game though. I just can’t get into the post-victory stuff. Ultimately it gets too repetitive, and leveling to level 100 just is plain tedious. My only Level 100 is a Palkia I got in an Internet trade. I was able to clean up in the online trading once I had Ditto to manufacture eggs of anything in Pearl, plus starter types from the LeafGreen I bought (for this purpose plus the purpose of just getting Daniel Squirtle, Charmander, Bulbasaur, Jiggypuff, and others).
Thoguh Daniel sure had me going longer in this than I went in either of the other ones I played (Blue on an emulator, Ruby on the GBA SP).