It's gonna be a long time before you can get Snorlax, so you might want to consider a place holder til then or just stick to having 5 Pokemon for the Johto part of the game. Anyway, it's only in-game, so any team can be considered good. What you have so far seems just fine. As for the last two Pokemon, I recommend Flareon or Arcanine (I don't know if you're playing HG or SS though, so if it's SS, then Ninetales instead of Arcanine). Fire types will help immensely against Jasmine and Koga. A final Pokemon to consider might be an electric type like Ampharos or Raichu. But your last two Pokemon should really be up to you. Try to choose Pokemon you personally like. You don't have to have a god-like team for in-game, so don't sweat it too much.
