My main gripe with Safari is that its release schedule is basically tied to OS releases. Ever since Chrome, I've come to love continuous releases. It's extremely satisfying to know that your browser will receive those important security updates quickly.
With Safari I have to deal with the App store nonsense (I still can't believe how bad that application is), waiting for stuff because Apple wants major releases to happen with their busted OS releases (your OS is free now! Please do rolling releases).
And I'm not a fan of Apple's positioning for web apps compared to Google or Mozilla. I like fancy new features!
The OS integration is, of course, better. Looks nice to use. And I think Chrome halves my battery life at this point. I should give it a shot again.