If i update an odoo database with -u all or if i update the base addon it will restore also all xml views like "website menu entries" and xml data like "Task States"! This is very annoying since after the update one needs to delete/restore all of theses items.
Is there a way to do a -u all without restoring Website Menu Entries or Task States and other existing Data?
Yes, you should apply all the changes you listed using custom module, then all the changes will be persisted through updates and you'll not lose your customizations anymore. So instead of changes using developer mode, implement a module and apply these changes from it.