To be honest, I don't see a use for a mouse on the Chromebook. Here is your new best friend: ctrl+alt+/
Learn shortcuts and rarely ever use the mouse or trackpad again. I did turn up the sensitivity to the trackpad for simple things (I use the three finger horizontal and vertical swipe as well as tap instead of click). Also go to chrome://flags and enable some really useful settings. This forum is pretty small as far as Chromebook discussion goes, so I would advise joining the Chromebooks Google+ community. Other than that, make sure that you're aware of Chrome Remote Desktop. I use it in case I forget a file on my desktop. Remotely log in, drop it in Google Drive, and access it on my CB.
I've had mine for three days and will never go back to a traditional laptop again! My 5 year old Macbook Pro will be replaced by a high end Chromebook later this year.