Do you really want to trust a giant company like Google to make privacy choices for you? No! Take control. Google has a redesigned account page that should make it easier to understand exactly what you're handing over to the big G.
The new My Account page doesn't offer you any new privacy and security options, it simply makes these settings easier to configure so that they're to your taste.
The first thing you should probably do, especially if you've never tweaked your setting before is run the new Privacy Checkup and Security Check Up.
The Privacy Checkup runs you through what information Google is storing and displaying across its services, and allows you to turn it on and off. And remember, if you turn off data history at all, you'll need to separately clear your existing history.
The upside to handing over some data is that it allows Google to tailor services to you. The downside is that if you hand everything from location to browsing history over, Google's got a very detailed record of what you do online and where you go. (I personally leave a lot of my settings on because I like personalised services, but you wouldn't be wrong if it creeps you out and you prefer to turn off data tracking.)
The Security Checkup runs you through important access settings for your account. It allows you to setup 2-factor authentication (which you should do), and shows you what devices and services have been accessing you account. There's a handy "security events" tab that lists recent changes to your security settings. For example, I recently revoked privileges to an old calendar app I signed up for years ago.
I've said it before: If you don't take control of your privacy settings on your various accounts, they will be taken care of for you.