Should I or shouldn't I?

So I have a copy of HeartGold and I've had it for over 2 years now. I've played 380 hours on it and I have a lot of pokémon on it.

But now... it's getting a bit dull...
My pokémon are all having a bad nature and are horribly trained. I have all 16 badges and because of the weakness of my pokémon I can't battle normally because I keep losing.

As for my question, should I start over? I have some fond memories of it, but I "replaced" it with pokémon black, though I really want to play in the first two regions again, but then with a better team.

So... should I start over?