Sweet, and sure! We can also use our old ones if we want. He did say he was rearranging boxes, and he didn’t say that he was putting anyone back in the real world
I actually put in the character sheets page a bit ago, but the levels are physically determined at level 2 based on the capabilities of the person in what they could do in real life. Everything else is just them getting stronger as they gain experience and knowledge.
The best and worst part is that even when they are old and grey, the stats remain. So if they were old when they spawned, they might be doomed, but if they started young, they will not fatigue with age.