The numbers differ for each user and is based on how much you have claimed from the faucet in the past vs how much you have played dice/lottery. So for someone who has only claimed a small amount from the faucet, reaching the next level will be much easier.
That is not true. For example if someone open new account right now: what he need to reach next level?
The bonus calculation only starts after your first free roll. Someone who has only claimed 100 satoshi will reach the next level much easier than someone who has claimed 10,000 satoshi but the 100 satoshi user will also drop levels much quicker when he makes higher claims.