Indeed, Google is inflexible on base, but they're well known (or at least I have it on fairly good authority) that they will match total comp of new grad offers from various finance firms, which have first year comp at ~200K.

And as to your second question: a rule of thumb that I think exists is that total comp approximately doubles every 2 levels, so you get a ~40% increase per level on the median. Keep in mind that a new grad offer is not the median of L3, but the bottom.