I find the Google account switcher - whilst not perfect (not being able to change the "Default" account is annoying), better than many other web services.

However, one thing I've found helpful - Chrome's inbuilt account switcher.

You can access this by clicking on the button in the top-right - basically, you can be signed into multiple Google accounts, one per Chrome window - and they will each have their own cookies, tabs etc.

So it's a good way of keeping things segregated.