Custom message upon complete ajax response

It would be logical and more flexible if the following messages:

'feedbackVoteSaved' => t('Your vote has been saved.'),
'feedbackVoteDeleted' => t('Your vote has been deleted.'),

... would be populated from the ajax response instead of like now being hard-coded into the js to display upon a successful request. This allows for more customized responses such as "Thanks for your vote, ", "Your vote has been updated" etc.

Also, in extension, this makes it easier to report back errors and exceptions upon response such as "You are not currently logged in, login to vote" and "Something went wrong when saving/deleting your vote, please refresh the page try again"