Q: iMac 5K El Capitan Safari and Magic Mouse II Freezes

My new iMac 27" 5K with company installed El Capitan seems to be having several issues. Routinely, approximately 80% of the time after waking from sleep, my Safari browser will fail to load a page. I'll type a search in the bar, and Safari just hangs. I can quit Safari and restart it, try the search again, and everything runs just fine.

Additionally, I've run into problems with my Magic Mouse II randomly becoming sluggish, especially within a game. I need to switch the mouse off, then back on again to make it work better again. I've since purchased a wired mouse and have had no problems, but I miss the magic mouse II functionality.

Not sure if anyone else is experiencing these problems.

Here are the specs:

iMac 27" 5K i7

32GB RAM

3TB Fusion Drive

El Capitan 10.11.3

  Model Name: iMac

  Model Id