I'm not sure if it's the overly large smile or what, but I find the current thanks-related Echo notification icon to be a bit disturbing. I'll upload a copy of it for reference momentarily.
Version: master
Severity: enhancement
See Also:
https://bugzilla.wikimedia.org/show_bug.cgi?id=41484
https://bugzilla.wikimedia.org/show_bug.cgi?id=56815