Just a quick suggestion. It seems there are several membership groups that are not used, and it clutters up the pull down menu (and is a tad confusing) when searching for members (or searching for posts by specific groups, etc.).
"Basic Member" is listed twice (the first time not having any members as part of that group)
"Basic Membre" is listed, and makes no sense really
"editor" contains one person that has 0 posts
"Security" contains one person that has only 3 posts
Also "Validating FullMember" and "Validating Member" are both listed. Those might be still be needed for temporary holding for validating members or something? ("Validating FullMember" contains nobody, but "Validating Member" contains 2 people with 0 posts)
Would there be a way to get rid of the excess groups, or merge them with the existing ones to reduce clutter? It may be more complicated than I thought, but if it is relatively simple I think it would be a good move.