We now have a nifty new feature expanding user cards to provide information about ourselves to other users. A minor problem is that it is comparatively awkward to see what your own user card looks like and if necessary tweak it if you want to make minor adjustments.
In keeping with the site theme of live preview, it would be very convenient if there were, for example, a test avatar to the left of the "About Me" text area on the profile editing page that could be used to exercise the expanding user card feature.
Here is an one possible implementation:
Then hover over the "User Card Preview" avatar: