Changing my iCloud account
Changing the email shouldn’t make a difference. If you delete the account and make a new one backup information could be lost.

From this Apple Discussion:


  When you delete the account and choose Keep on My iPhone (iPad), contacts, calendars and other synced data will remain on your device.  When you sign in with your new ID to create your new account and choose Merge, these will be uploaded to your new account.  Synced notes and photo stream photos are exceptions to this, which is why you have to take steps to save them prior to deleting the account.