If you've beaten the Main Scenario, you should have the option to carry that over.

[AdamFyi]

Those things are completely different. Those things actually effect game balance, my suggestion applies only to Main Scenario which doesn't do anything.

Again, you're not really thinking it through. There are certain limitations to this. Namely, the fact that you can't complete level 60 quests with a level 1 character. Some of the MSQ quests also unlock other functions of the game. How are you going to implement it without breaking the game?