remove user edit button (globla) - commit deleted comments

Hi there,
two things:

1.) is there a possibility to disable the edit button complety (also not avalible through an url) to spezific user roles?
2.) If a user delete his/her comment on a nodetype could it be possible to set this comment to not visible and the nodecreator must commit this? For example a user types a comment on a userprofile and delete this comment. The owner will never know what there stood. (Maybe Spam, Defamations or so)

i think this modul is long ago overdue.

king regards