Backups – Best Practices

My site is about to go live, finally, and I’m working through how to backup my database and files. Could someone who is running a medium to large multisite install please advise how often someone should backup the database and site files. I’m thinking database daily and site files weekly.

Also, I would really prefer to keep my backups on my local machine but I’ve read in several posts here that cPanel backups can choke once your db or file sizes get too big. Can someone who is keeping their backups on their local machine advise how they are handling the process.