Above Sr. SWE my impression is that the level is less tightly coupled to compensation. There are probably some Staff Engineers getting paid more than some Sr. Staff, and so on. A lot more will depend on how many rounds of equity refresh you have under your belt, whether you've done something that's saved the company millions or helped the bottom line of the company millions; and of course, if you were formerly at another company, what your salary/level you had at that former company.
At Staff Engineer and above, the levels are more about the scope of your responsibilities at Google, and while compensation is somewhat correlated to that, there are other factors.
If you can drive huge amounts of value to the bottom line, either via innovations that save the company $$$ or by working on a project which is "up and to the right", in my experience sooner or later you will be compensated for it --- either at your current company, or somewhere else. Google is pretty good at making sure it's "at your current company".
And so long as you are doing something that you love, does it really matter what level you are at? Personally, for me it's less about the money, since I have enough to be comfortable, and I haven't gotten really expensive habits (like wanting to learn how to fly, or drive race cars, or children to put through college :-). So it's it's more about doing what I love, and doing it in the company of smart people who are fun to be with. Figuring ways of making this intersect with adding as much value as possible to the company is just a bonus.