I also did all the extra areas, including grind up to where i could take them, do you recommend i restart on launch, as i might be over leveled for the next couple areas.
Levels are useful (the testers tend to beat the game around level 30) but aren't a guarantee. Equipment is also really important, so playing the game with an extra high level is only going to make the next few areas easier, but not super duper easy. Still, if you're looking for a challenge then you can restart. It only takes about 20 minutes (if you know what you're doing) to clear the demo's content without grinding. You can actually beat Quinn at level 1 with some luck!