I have another suggestion as well.
Add in an appeal button. The ban appeals would go on a page like an inbox, only for all the admins and moderators to see. Such as with sourcebans, there is a ban request and ban appeals system built in.
http://www.sylesrp.com/sourcebans/index.php?p=protest <-- example page of sourcebans, and if you look around you could probably find a link to post a ban request, but that might actually be an admin-only thing on that sourcebans feature because I only see it when I log on to that sourcebans site with my admin account.
Also note the link above is NOT meant to be as an advertisement. The server using that page isn't even Minecraft lolz.