Recently caught some emails going around about recommended backup and maintenance plans as it relates to ConfigMgr. Also plenty of discussions around whether or not addition index optimization is required beyond the built-in Rebuild Indexes task that can be configured as part of the built-in Site Maintenance task.
As far as what I recommend and configure for the clients I work with. I use the recommendations from Steve Thompson a fellow MVP and former SQL MVP.
I would highly recommend you read through the above linked posts. The maintenance plan is what I use for backing up the CM database and supporting databases. I do not use the built-in backup task with ConfigMgr 2012.
If you are having issues with indexing or slow performance, then it’s a good idea to look into the index optimization recommendations as well.