Call yourselves paranoid?
Jeeze!
You guys are really NOT paranoid at all!
For example (above):
"I've got Firefox set to delete all cookies every session so as it crashes every week or so, I get to clear the cookies fairly regularly."
'Every week or so' is not even 'fairly' regularly. Every few minutes is regularly.
I use FF's 'clear private data' (Ctrl+Shift+Del) virtually every time I change a page and I have FF set to delete all private data at closing. If using webmail I close FF, Stephen Gould's 'CleanUp!', then re-open to continue browsing. (In fact, I use Gould's 'CleanUp!' a lot).
Another example (above)
"I'd get annoyed if I had to turn 'safe search' off every few days again." Convenience (or laziness) triumphing over security? I mean just how onerous is changeing the search preference in Google?
Changing a preference on a serverside app means another cookie so I use FF's delete private data immediately after any session which places cookies (which might mean half-a-dozen times an hour).
Also, because my ISP allocates dynamic IP addresses, I tend to break the connection fairly frequently during the day (takes only a few seconds to re-connect) which slightly inhibits Google establishing a direct linkage between search sessions.
I don't search for porn: I don't run scams: I'm not planning to kill anyone or blow up parliament. In fact, I've got nothing to hide. But that's besides the point: I value my privacy and I'm prepared to suffer a few minutes daily inconvenience to retain some of it.
If I wanted to do anything nasty online (which I don't) I'd at least go to the trouble of doing it from behind Tor or using a public computer (in a town away from my home area).
As for Google "doing no evil" and being a cuddly outfit run by groovy laid-back hipsters Serge and Larry... what utter bollocks! Google is a huge, aggressively-acquisitive, rapidly-expanding, information-hoarding multinational corporation. The less a commercial entity like that knows about me, the better.