We've just let 1.10 lose on some real-life testers and the first comment I had wasn't entirely flattering about the avatars. Let's just say that I would be more comfortable if we could turn them off (and perhaps come back to them later). In this context I do think 'off' could be equivalent to a set that's just some coloured blobs (but nothing else) if that makes it easier.
I am not particularly a fan of utilizing avatars in an environment where the ticketing system is possibly their first impression of the IT team. I would surmise you could always just replace the images with those that are different and more appealing like self images.
"You" in this case being the user, which isn't really satisfactory if they already have a negative attitude to the feature, which is why I'd rather prefer to be able to turn the feature off for everyone at the outset.