For atto/tinymce editors the translation will remain connected even if the source text changes - you even get shown a diff of the original and updated source text when you re-translate.
Backup and restore is not currently supported but definitely could be.
It sounds like you've taken a very different approach to using a filter so it may be that this isn't a direct fit but I would definitely be interested in your feedback.
General developer forum
Looking for beta-testers of a Course Translator Plugin
Гэтае абмеркаваньне было заблакавана, таму вы болей ня можаце адказваць на яго.