Mail editor defaulting to Ckeditor and text wrap issue
I strongly suspect that what you're seeing is a side effect of CiviCRM dropping support for TinyMCE in core.  If upgrading to 4.7 is an option, I suspect that you can solve this problem by installing the TinyMCE extension.

Of course, if CiviMail is important to you, then upgrading to 4.7 shouldn't happen until these two bugs are closed in a released version of CiviCRM:


https://issues.civicrm.org/jira/browse/CRM-17968
https://issues.civicrm.org/jira/browse/CRM-17953